Co-reporter:Guangwei Geng, Penglei Chen, Bo Guan, Lang Jiang, Zhongfei Xu, Dawei Di, Zeyi Tu, Weichang Hao, Yuanping Yi, Chuncheng Chen, Minghua Liu, and Wenping Hu
ACS Nano May 23, 2017 Volume 11(Issue 5) pp:4866-4866
Publication Date(Web):April 17, 2017
DOI:10.1021/acsnano.7b01427
Metal-free catalytic materials have recently received broad attention as promising alternatives to metal-involved catalysts. This is owing to their inherent capability to overcome the inevitable limitations of metal-involved catalysts, such as high sensitivity to poisoning, the limited reserves, high cost and scarcity of metals (especially noble metals), etc. However, the lack of shape-controlled metal-free catalysts with well-defined facets is a formidable bottleneck limiting our understandings on the underlying structure–activity relationship at atomic/molecular level, which thereby restrains their rational design. Here, we report that catalytically active crystals of a porphyrin, 5,10,15,20-tetrakis(pentafluorophenyl)porphyrin, could be shaped into well-defined cubes and sheet-like tetradecahedrons (TDHD), which are exclusively and predominantly enclosed by {101} and {001} facets, respectively. Fascinatingly, compared to the cubes, the TDHDs display substantially enhanced catalytic activity toward water decontamination under visible-light irradiation, although both the architectures have identical crystalline structure. We disclose that such interesting shape-sensitive catalytic activity is ascribed to the distinct spatial separation efficiency of photogenerated electrons and holes induced by single-channel and multichannel charge transport pathways along noncovalent supramolecular chains, which are arranged as parallel-aligned and 2D network patterns, respectively. Our findings provide an ideal scientific platform to guide the rational design of next-generation metal-free catalysts of desired catalytic performances.Keywords: 2D charge transport network; facet-sensitive catalytic activity; metal-free catalysts; noncovalent supramolecular chains; organic crystals;
Co-reporter:Guangwei Geng;Bo Guan;Mingshan Zhu;Changchun Yang;Minghua Liu
RSC Advances (2011-Present) 2017 vol. 7(Issue 16) pp:9948-9957
Publication Date(Web):2017/01/30
DOI:10.1039/C6RA27462E
Graphite (Gr)-based composite materials have been attracting great interest from the scientific and engineering communities. While tremendous progress has been achieved in this field, it still remains a formidable challenge to hybridize pristine Gr with other components under ambient conditions without breaking the π-conjugated system of Gr. Herein, we report that Gr could be facilely hybridized with visible-light-driven plasmonic photocatalyst Ag/AgBr with the assistance of graphene oxide (GO) nanosheets under ambient conditions. We demonstrate that without the use of GO, Gr could not be well hybridized with Ag/AgBr, while a good hybrid Gr/GO/Ag/AgBr could be produced when GO nanosheets are introduced into the system. Our results show that compared to Ag/AgBr, GO/Ag/AgBr and Gr/Ag/AgBr species, thus-fabricated Gr/GO/Ag/AgBr hybrids could display substantially enhanced catalytic activity towards the photobleaching of methyl orange under visible-light irradiation. It is disclosed that the good hybridization between Gr and Ag/AgBr, which is mediated by GO, and the facilitated separation of photogenerated electrons and holes, which is promoted both by GO and Gr, contribute much to the boosted catalytic performances. Considering the excellent hybridization capability of GO, the exceptional electronic characteristics, versatile multifunctionality and low-cost of Gr, our protocol might be applicable not only to the Ag/AgBr-based plasmonic photocatalysts but also to a wide variety of other functional materials, wherein Gr/GO-based advanced materials of desired and reinforced functions or properties might be inaugurated.
Co-reporter:Guangwei Geng;Bo Guan;Yu Liu;Changchun Yang;Nannan Wang;Minghua Liu
RSC Advances (2011-Present) 2017 vol. 7(Issue 82) pp:51838-51846
Publication Date(Web):2017/11/07
DOI:10.1039/C7RA11188F
Au nanoarchitectures shaped with a sheetlike morphology have drawn great attention owing to their potential applications in diverse areas of paramount importance. While great achievements have been made in the fabrication of Au nanoplates, most of the currently existing synthesis protocols generally suffer from either the requirement of rigorous reaction conditions, the involvement of specific apparatus, the use of harmful chemicals, etc. The initiation of an easy, environmentally benign yet low cost method to avoid these issues is strongly desired. In this contribution, we find that Au nanoplates could be fabricated under ambient conditions simply by mixing an aqueous solution of potassium tetrachloroaurate(III), an aqueous dispersion of graphene oxide (GO), and ethanol. Interestingly, we show that the as-manufactured Au nanoplate/GO composite displays fascinating two-stage catalytic performance towards NaBH4-induced reduction of 4-nitrophenol (4-NP), in which the catalytic reactivity of the latter stage exhibits a substantial enhancement by a factor of ca. 9 times compared to that of the former stage. Our investigation suggests that such fascinating catalytic behaviors could be ascribed to the NaBH4-induced restoration of the π-conjugated aromatic network of GO during the first stage, which promotes electron transfer from GO to Au nanoplates and facilitates the anchoring of 4-NPs onto the composites, resulting in the dramatically boosted catalytic performance of the second stage. This work might not only introduce a facile, green yet low-cost protocol for the synthesis of Au nanoplates but also provide deep insights into the catalytic performances of GO-based hybrid catalysts in terms of an interesting two-stage catalytic behavior.
Co-reporter:Dan Xiao;Guangwei Geng;Tiesheng Li;Minghua Liu
Physical Chemistry Chemical Physics 2017 vol. 19(Issue 1) pp:837-845
Publication Date(Web):2016/12/21
DOI:10.1039/C6CP06948G
Silver halide-based structures have been attracting great interest as efficient visible-light-driven photocatalysts towards the photodegradation of organic pollutants, and those studies focusing on their morphology-dependent catalytic performances have received particular attention. While great advancements in this regard have been witnessed in the past few years with respect to AgCl- and AgBr-based photocatalysts, relevant explorations concerning AgI-based species are relatively rare, even though the excellent durability of AgI-based structures renders them attractive candidates for potential photocatalytic uses. By means of chemical reactions between AgNO3 and tetramethylammonium iodide (TMAI), and AgNO3 and tetrabutylammonium iodide (TBAI), we herein report that AgI structures with a sheet-like and a truncated-dodecahedron-like morphology, respectively, could be controllably synthesized via a surfactant-assisted fabrication protocol. In our synthesis systems, AgNO3 works as the silver source, while the TMAI and TBAI surfactants serve not only as an iodine source but also as a directing reagent for controllable fabrication. It has been demonstrated that our AgI structures could work as visible-light-energized photocatalysts towards the photodegradation of methyl orange. We find that compared to their sheet-like counterparts, the truncated-dodecahedron-like AgI architectures exhibit substantially boosted catalytic performances. Moreover, we disclose that our truncated-dodecahedron-like AgI-based species could display excellent photocatalytic stability, wherein their catalytic reactivity displays only trivial fluctuations under visible-light irradiation even after the photoreactions have been repeated 22 times continuously. Our work might not only introduce a facile protocol for the controllable synthesis of AgI structures but also pave an avenue for facile enhancement of their catalytic performances via morphology alterations.
Co-reporter:Xiao Zhang, Yanping Wang, Penglei Chen, Yunlong Rong and Minghua Liu
Physical Chemistry Chemical Physics 2016 vol. 18(Issue 20) pp:14023-14029
Publication Date(Web):25 Apr 2016
DOI:10.1039/C6CP00683C
Porphyrins are considered to be important scaffolds bridging supramolecular chemistry and chiral chemistry, where chirality selection via physical effects such as directional stirring and spin-coating has aroused particular interest. Nevertheless, these protocols could only work on a limited number of achiral porphyrins. It still remains a formidable challenge to pave a general avenue for the construction of chiral assemblies using achiral porphyrins. By means of a unique Langmuir–Schaefer (LS) technique of a unidirectional compression configuration, we herein have demonstrated that a series of achiral porphyrins could be facilely organized to form chiral interfacial assemblies of controlled supramolecular chirality. It has been disclosed that such a fascinating chirality selection scenario is intimately related to the direction of the compression-generated vortex-like flow, while the compression speed, one of the most significant parameters of the Langmuir technique, contributes less to this issue. With regard to a surface-pressure-dependent chirality selection phenomenon, it is suggested that the directional vortex-like flow generated by lateral compression might play a role in promoting the preferential growth of chiral assemblies showing an enhanced yet controlled CD signal. Our protocol might be, to some extent, a general method for achieving chiral porphyrin assemblies of controlled chirality.
Co-reporter:Congcong Zhang, Penglei Chen and Wenping Hu
Chemical Society Reviews 2015 vol. 44(Issue 8) pp:2087-2107
Publication Date(Web):02 Mar 2015
DOI:10.1039/C4CS00326H
Organic field-effect transistors (OFETs) are one of the key components of modern organic electronics. While the past several decades have witnessed huge successes in high-performance OFETs, their sophisticated functionalization with regard to the responses towards external stimulations has also aroused increasing attention and become an important field of general concern. This is promoted by the inherent merits of organic semiconductors, including considerable variety in molecular design, low cost, light weight, mechanical flexibility, and solution processability, as well as by the intrinsic advantages of OFETs including multiparameter accessibility and ease of large-scale manufacturing, which provide OFETs with great potential as portable yet reliable sensors offering high sensitivity, selectivity, and expeditious responses. With special emphases on the works achieved since 2009, this tutorial review focuses on OFET-based gas sensors. The working principles of this type of gas sensors are discussed in detail, the state-of-the-art protocols developed for high-performance gas sensing are highlighted, and the advanced gas discrimination systems in terms of sensory arrays of OFETs are also introduced. This tutorial review intends to provide readers with a deep understanding for the future design of high-quality OFET gas sensors for potential uses.
Co-reporter:Congcong Zhang;Huanli Dong;Yonggang Zhen;Minghua Liu;Wenping Hu
Advanced Materials 2015 Volume 27( Issue 36) pp:5379-5387
Publication Date(Web):
DOI:10.1002/adma.201501273
One-dimensional (1D) solid-state supramolecular structures based on porphyrin chromophores arouse numerous expectations from the interdisciplinary scientific communities of supramolecular chemistry and advanced soft materials science. This stems from the intrinsic assembly capability of porphyrins to form various well-defined 1D assemblies, which have broad opportunities in the fields of advanced soft matter. A brief review on 1D porphyrin micro-/nanoassemblies constructed via surfactant-assisted self-assembly is presented here, in terms of addressing new ideas recently developed for controlled assembly, hierarchical organization, and new-type functional surfactants etc. The functionalization of the as-assembled 1D structures with regard to supramolecular photocatalysis, non-linear optics, nanoelectronic gas sensors, photoelectrochemical solar cells, etc. is highlighted.
Co-reporter:Yanping Wang, Penglei Chen, Yunfan Shen, Chuncheng Chen, Changchun Yang and Minghua Liu
Physical Chemistry Chemical Physics 2015 vol. 17(Issue 38) pp:25182-25190
Publication Date(Web):24 Aug 2015
DOI:10.1039/C5CP03618F
Ag/AgCl-based plasmonic photocatalysts have received much attention as emerging visible-light-driven photocatalysts, wherein those characterized by 1D morphology have aroused great expectations. Most of the current existing protocols for the fabrication of 1D materials, however, suffer from either multistep tedious synthesis processes or the requirement of rigorous experimental conditions. A one-pot fabrication method feasible under ambient conditions is strongly desired. By means of a surfactant-assisted protocol, we report herein that Ag/AgCl structures of near-spherical and 1D morphology could be controllably produced. We show that near-spherical Ag/AgCl species could be produced immediately after dropping an AgNO3 aqueous solution into an aqueous solution of cetyltrimethylammonium chloride (CTAC) surfactant under stirring. Interestingly, we show that these initially formed near-spherical species could automatically evolve into 1D Ag/AgCl fibers simply by extending the stirring time under ambient conditions. In our new protocol, CTAC works not only as a chlorine source but also as a directing reagent to assist the formation of 1D Ag/AgCl structures. Moreover, we demonstrate that compared to near-spherical structures, our Ag/AgCl fibers could display boosted catalytic performances towards the photodegradation of the methyl orange pollutant under visible light irradiation. Our work might launch an easy method for the construction of fibrous Ag/AgCl architectures of superior photocatalytic reactivity, and it also provides deep insights into the surfactant-assisted synthesis.
Co-reporter:Xiao Zhang, Mingshan Zhu, Penglei Chen, Yongjun Li, Huibiao Liu, Yuliang Li and Minghua Liu
Physical Chemistry Chemical Physics 2015 vol. 17(Issue 2) pp:1217-1225
Publication Date(Web):14 Nov 2014
DOI:10.1039/C4CP04683H
Advanced functional hybrids based on carbon materials (CMs) represent one of the main achievements of scientific communities. To achieve the hybridization, pristine CMs have to be chemically modified, or surfactants, which are nonfunctional for the performances of the hybrids, have to be employed as a cross-linkage. The construction of pristine CM-based hybrids using dual-functional coupling reagents, which work not only as a glue for hybridization but also as a functional component for enhanced performance, is strongly desired. Here, we report that pristine graphdiyne (GD), a recently synthesized new carbon allotrope, can be facilely hybridized with Ag/AgBr using graphene oxide (GO) as a cross-linkage. We demonstrate that compared to Ag/AgBr, Ag/AgBr/GO, and Ag/AgBr/GD, our Ag/AgBr/GO/GD exhibits an enhanced photocatalytic performance toward the degradation of methyl orange (MO) pollutant under visible light irradiation. In our Ag/AgBr/GO/GD, GO serves not only as a glue for a successful hybridization, but also as a functional component for enhanced catalytic performance. Beyond GD, our work likely paves a new avenue for the fabrication of advanced functional hybrids based on pristine carbon allotropes, wherein desired functions or properties might be achieved by choosing desired CMs and desired hybridized components.
Co-reporter:Xiao Zhang, Yanping Wang, Penglei Chen, Peipei Guo and Minghua Liu
RSC Advances 2015 vol. 5(Issue 96) pp:78427-78435
Publication Date(Web):07 Sep 2015
DOI:10.1039/C5RA13283E
The assembly of π-conjugated molecule-based supramolecular micro/nanostructures is acknowledged as a versatile platform correlating supramolecular chemistry and soft matter science, wherein those with a spherical morphology are a topic of general concern. Most of the existing protocols, however, work only in some specific scenarios. It still remains a formidable challenge to initiate a general protocol for supramolecular micro/nanospheres of desired π-conjugated molecules. We herein report our new findings that numerous porphyrins and some other π-conjugated molecules, including phthalocyanine, anthracene, and naphthalenediimide derivatives, could be assembled to form micro/nanospheres via an oil-in-water-mediated surfactant-assisted assembly. As an example for the functionalization of the as-assembled structures, we show that a supramolecular light-harvesting antenna system with regard to photo-semiconductor-based heterogeneous photocatalysis could be achieved using porphyrin spheres. It is disclosed that the distinct chromophoric arrangements, which endow our porphyrin spheres with different photoinduced electron–hole separation capability, contribute greatly to their superior/inferior catalytic performances. Our new method might initiate a general method for advanced micro/nanospheres of desired π-conjugated molecules and desired functions.
Co-reporter:Yunfan Shen, Penglei Chen, Dan Xiao, Chuncheng Chen, Mingshan Zhu, Tiesheng Li, Wangong Ma, and Minghua Liu
Langmuir 2015 Volume 31(Issue 1) pp:602-610
Publication Date(Web):December 9, 2014
DOI:10.1021/la504328j
We herein report that spherical and sheetlike Ag/AgCl nanostructures could be controllably synthesized by means of chemical reactions between AgNO3 and cetyltrimethylammonium chloride (CTAC) surfactant. In this synthesis system, AgNO3 works as the silver source, while CTAC serves not only as the chlorine source but also as the directing reagent for a controllable nanofabrication. We show that compared to the spherical Ag/AgCl nanostructures, the sheetlike counterparts, wherein the AgCl nanospecies are predominantly enriched with {111} facets, could exhibit superior catalytic performances toward the photodegradation of methyl orange. Interestingly, we further demonstrate that when 4-chlorophenol or phenol is used as the substrate, the sheetlike Ag/AgCl nanostructures exhibit inferior catalytic reactivity, whereas the spherical counterparts display superior catalytic performances comparatively. Our results disclose new insights on the facet-dependent catalytic performances with regard to a facet-selective but substrate-sensitive photoinduced electron–hole separation.
Co-reporter:Xiaowei Ou;Lang Jiang;Yunfan Shen;Wenping Hu;Minghua Liu
Advanced Functional Materials 2014 Volume 24( Issue 4) pp:543-554
Publication Date(Web):
DOI:10.1002/adfm.201302153
Graphene-based ultrathin films with tunable performances, controlled thickness, and high stability are crucial for their uses. The currently existing protocols, however, could hardly simultaneously meet these requirements. Using amino-substituted π-conjugated compounds, including 1,4-diaminobenzene (DABNH2), benzidine (BZDNH2), and 5,10,15,20-tetrakis (4-aminophenyl)-21H,23H-porphine (TPPNH2), as cross-linkages, a new protocol through which graphene oxide (GO) nanosheets can be anchored on solid supports with a high stability and controlled thickness via a layer-by-layer method is presented. A thermal annealing leads to the reduction of the films, and the qualities of the samples can be inherited by the as-produced reduced GO films (RGO). When RGO films are integrated as source/drain electrodes in OFETs, tunable performances can be realized. The devices based on the BZDNH2-crosslinked RGO electrodes exhibit similar electrical behaviors as those based on the non-π-conjugated compound crosslinked electrodes, while improved performances can be gained when those crosslinked by DABNH2 are used. The performances can be further improved when RGO films crosslinked by TPPNH2 are employed. This work likely paves a new avenue for graphene-based films of tunable performances, controlled thickness, and high stability.
Co-reporter:Liping Wang, Xiaodong Xie, Weifeng Zhang, Ji Zhang, Mingshan Zhu, Yunlong Guo, Penglei Chen, Minghua Liu and Gui Yu
Journal of Materials Chemistry A 2014 vol. 2(Issue 32) pp:6484-6490
Publication Date(Web):03 Jul 2014
DOI:10.1039/C4TC00251B
High-performance organic phototransistors (OPTs) have been successfully constructed using bitriisopropylsilylethynyl tetraceno[2,3-b]thiophenes (TIPSEthiotet) or pentacene as a semiconductor layer. Fluorographene (FG) nanosheets were used to modify the interface between an organic semiconductor layer and gate dielectric. The effects of interface modification were investigated. It was found that enhanced photoresponsivity and a boosted photocurrent/dark-current ratio could be easily achieved after the implantation of modification layers. The constructed FG-modified devices based on TIPSEthiotet showed a maximum photoresponsivity of 21.83 A W−1 and a photocurrent/dark-current ratio of 1.85 × 106 under white light irradiation. Meanwhile, for the FG-modified OPT device based on pentacene, a high photoresponsivity of 144 A W−1 was obtained under white light irradiation with an optical power of as low as 25 μW cm−2. This photoresponsivity datum is higher than that of most OPTs based on pentacene reported under the same conditions. In addition, the mobilities of the devices could also be increased distinctly after the introduction of the FG-modified layer. The experimental facts indicate that the strong electron trapping ability of the fluorine atoms in the FG nanosheets and the well-known photovoltaic effect play an important role in these interesting results.
Co-reporter:Bin Lei, Mingshan Zhu, Penglei Chen, Chuncheng Chen, Wanhong Ma, Tiesheng Li, and Minghua Liu
ACS Applied Materials & Interfaces 2014 Volume 6(Issue 6) pp:4160
Publication Date(Web):February 25, 2014
DOI:10.1021/am405816p
The fabrication of microstructures/nanostructures of a uniform yet well-defined morphology has attracted broad interest from a variety of fields of advanced functional materials, especially catalysts. Most of the conventional methods generally suffer from harsh synthesis conditions, requirement of bulky apparatus, or incapability of scalable production, etc. To meet these formidable challenges, it is strongly desired to develop a facile, cost-effective, scalable method to fulfill a morphology purification. By a precipitation reaction between AgNO3 and KI, we report that irregular AgI structures, or their mixture with towerlike AgI architectures could be fabricated. Compared to the former, the mixed structures exhibit enhanced catalytic reactivity toward the photodegradation of Methyl Orange pollutant. However, its catalytic durability, which is one of the most crucial criteria that are required by superior catalysts, is poor. We further show that the irregular structures could be facilely removed from the mixture via a KI-assisted chemical dissolution, producing AgI of a uniform towerlike morphology. Excitingly, after such simple morphology purification, our towerlike AgI displays not only a boosted catalytic durability but also an enhanced catalytic reactivity. Our chemical dissolution-based morphology purification protocol might be extended to other systems, wherein high-quality advanced functional materials of desired properties might be developed.Keywords: boosted catalytic durability; chemical dissolution; enhance catalytic reactivity; morphology purification; visible-light/sunlight-driven photocatalysts;
Co-reporter:Peipei Guo, Guangyao Zhao, Penglei Chen, Bin Lei, Lang Jiang, Hantang Zhang, Wenping Hu, and Minghua Liu
ACS Nano 2014 Volume 8(Issue 4) pp:3402
Publication Date(Web):March 24, 2014
DOI:10.1021/nn406071f
Porphyrins are recognized as important π-conjugated molecules correlating supramolecular chemistry, nanoscience, and advanced materials science. So far, as their supramolecular nanoassemblies are addressed, most efforts focus on the photo- or opto-related subjects. Beyond these traditional subjects, it is strongly desired to develop advanced porphyrin nanoassemblies in some other new topics of paramount importance. By means of a surfactant-assisted assembly, we herein show that porphyrins of different central metal ions, 5,10,15,20-tetra(4-pyridyl)-21H,23H-porphine (H2TPyP), zinc 5,10,15,20-tetra(4-pyridyl)-21H,23H-porphine (ZnTPyP), and oxo-[5,10,15,20-tetra(4-pyridyl)porphyrinato]titanium(IV) (TiOTPyP), could be organized to form irregular aggregates, short nanorods, and long yet straight nanofibers, respectively. Remarkably, in terms of an organic ribbon mask technique, we show that such long yet straight TiOTPyP nanofibers could be integrated into single nanofiber-based two-end nanoelectronics. Such simple nanodevices could serve as high-performance sensors of a satisfactory stability, reproducibility, and selectivity for an expeditious detection of vapor-phase H2O2. This provides a new alternative for a fast sensing of vapor-phase H2O2, which is currently an important issue in the fields of anti-terrorism, industrial healthcare, etc. In contrast to the traditional investigations focusing on the photo- or opto-related topics, our work endows porphyrin nanostructures with new opportunities as advanced nanomaterials in terms of portable yet high-performance nanoelectronic sensors, which is an issue of general concern in modern advanced nanomaterials.Keywords: nanoelectronic sensors; nanofibers; self-assembly; supramolecular nanomaterials; π-conjugated molecules
Co-reporter:Xiaowei Ou;Lang Jiang;Mingshan Zhu;Wenping Hu;Minghua Liu;Junfa Zhu;Huanxin Ju
Advanced Functional Materials 2013 Volume 23( Issue 19) pp:2422-2435
Publication Date(Web):
DOI:10.1002/adfm.201202586
Abstract
Highly stable graphene oxide (GO)-based multilayered ultrathin films can be covalently immobilized on solid supports through a covalent-based method. It is demonstrated that when (3-aminopropyl) trimethoxysilane (APTMS), which works as a covalent cross-linking agent, and GO nanosheets are assembled in an layer-by-layer (LBL) manner, GO nanosheets can be covalently grafted on the solid substrate successfully to produce uniform multilayered (APTMS/GO)N films over large-area surfaces. Compared with conventional noncovalent LBL films constructed by electrostatic interactions, those assembled using this covalent-based method display much higher stability and reproducibility. Upon thermal annealing-induced reduction of the covalent (APTMS/GO)N films, the obtained reduced GO (RGO) films, (APTMS/RGO)N, preserve their basic structural characteristics. It is also shown that the as-prepared covalent (APTMS/RGO)N multilayer films can be used as highly stable source/drain electrodes in organic field-effect transistors (OFETs). When the number of bilayers of the (APTMS/RGO)N film exceeds 2 (ca. 2.7 nm), the OFETs based on (APTMS/RGO)N electrodes display much better electrical performance than devices based on 40 nm Au electrodes. The covalent protocol proposed may open up new opportunities for the construction of graphene-based ultrathin films with excellent stability and reproducibility, which are desired for practical applications that require withstanding of multistep post-production processes.
Co-reporter:Yunlong Rong, Penglei Chen and Minghua Liu
Chemical Communications 2013 vol. 49(Issue 89) pp:10498-10500
Publication Date(Web):18 Sep 2013
DOI:10.1039/C3CC46467A
Water-soluble TPPS was found to self-assemble into long nanofibers of ambiguous chirality in organic solvents, while mirror imaged chiroptical nanorods with controlled chirality were formed when (1R,2R)-(−)- or (1S,2S)-(+)-1,2-diaminocyclohexane was involved during the self-assembly.
Co-reporter:Peipei Guo, Penglei Chen, and Minghua Liu
ACS Applied Materials & Interfaces 2013 Volume 5(Issue 11) pp:5336
Publication Date(Web):May 7, 2013
DOI:10.1021/am401260n
Surfactant-assisted self-assembly (SAS) has received much attention for supramolecular nanoassemblies, due to its simplicity and easiness in realizing a controllable assembly. However, in most of the existing SAS protocols, the employed surfactants work only as a regulator for a controllable assembly but not as active species for function improvement. In this paper, we report that a porphyrin, zinc 5,10,15,20-tetra(4-pyridyl)-21H,23H-porphine (ZnTPyP), could be assembled to form one-dimensional (1D) supramolecular nanostructures via a SAS method, wherein graphene oxide (GO) plays a fascinating role of sheetlike surfactant. We show that, when a chloroform or tetrahydrofuran solution of ZnTPyP is injected into an aqueous dispersion of GO, 1D supramolecular nanoassemblies of ZnTPyP with well-defined internal structures could be easily formulated in a controllable manner. Our experimental facts disclose that the complexation of ZnTPyP with the two-dimensional GO nanosheets plays an important role in this new type of SAS. More interestingly, compared with the 1D ZnTPyP nanoassemblies formulated via a conventional SAS, wherein cetyltrimethylammonium bromide is used as surfactant, those constructed via our GO-assisted SAS display distinctly enhanced photocatalytic activity for the photodegradation of rhodamine B under visible-light irradiation. Our new findings suggest that GO could work not only as an emergent sheetlike surfactant for SAS in terms of supramolecular nanoassembly but also as functional components during the performance of the assembled nanostructures.Keywords: graphene oxide; porphyrin; sheetlike surfactant; supramolecular nanoassemblies; surfactant-assisted self-assembly;
Co-reporter:Mingshan Zhu, Xiaodong Xie, Yunlong Guo, Penglei Chen, Xiaowei Ou, Gui Yu and Minghua Liu
Physical Chemistry Chemical Physics 2013 vol. 15(Issue 48) pp:20992-21000
Publication Date(Web):14 Oct 2013
DOI:10.1039/C3CP53383B
As the youngest in the graphene family, fluorographene has received numerous expectations from the scientific community. Investigation of fluorographene is similar to graphene and graphene oxide, wherein fabrication is an importance subject in the infancy stage. Fluorographene produced by the currently existing protocols, however, could only disperse in a limited number of solvents, and the dispersions generally exhibit short-term stability, restricting its manipulation and processing. To address this formidable challenge, we herein report that fluorographene nanosheets, most of which have a single-layered structure, could be easily formulated from commercially available graphite fluoride via a one-pot chloroform-mediated sonochemical exfoliation under ambient conditions without any pretreatment, special protection or stabilizers. Significantly, owing to the exceptional volatility of chloroform, our fluorographene originally dispersed in chloroform, could be facilely transferred into other 24 kinds of solvents via a volatilization–redispersion process, wherein dispersions of extremely long-term stability (more than six months) could be obtained. As an example to demonstrate the merit of the as-formulated fluorographene and its potential application possibilities, we further show that our fluorographene could be easily assembled as a modified layer in pentacene-based organic field-effect transistors simply by a spin-coating method, wherein distinctly increased mobility and positively shifted threshold voltage could be achieved. Considering the excellent popularity of chloroform in the scientific community, the remarkable volatility of chloroform, the broad solvent dispersibility of our fluorographene, and together with the long-term stability of the dispersions, our chloroform-mediated sonochemical exfoliation protocol likely endow fluorographene with new and broad opportunities for fabrication of graphene-based advanced functional films and nanocomposites via liquid-phase manipulation or solution-processing strategies.
Co-reporter:Mingshan Zhu, Chuncheng Chen, Penglei Chen, Bin Lei, Wanhong Ma and Minghua Liu
Physical Chemistry Chemical Physics 2013 vol. 15(Issue 30) pp:12709-12716
Publication Date(Web):21 May 2013
DOI:10.1039/C3CP51707A
The solid solution (SS) method is an effective way to design impactful photocatalysts, owing to its merit of continuous bandgap-tuning. A calcination, usually breaking the morphology of a material, has to be used to synthesize such catalysts, although the morphology is a critical issue affecting its catalytic behavior. It thus is strongly desired to construct SS-based catalysts with a shaped morphology. Here, we report that AgCl1–xBrx SS-based photocatalysts, Ag–AgCl1–xBrx, with a shaped morphology, can be produced via an ion-exchange between nanostructured Ag–AgCl and KBr. It is found that when sphere-like Ag–AgCl is employed as a precursor, the Ag–AgCl1–xBrx, maintains its morphology when x is in the range of 0–1. The bandgap, and the catalytic activities of these Ag–AgCl1–xBrx for the degradation of methyl orange, display a monotonic narrowing and a continuous enhancement, respectively, with the increase of x. In contrast, when cube-like Ag–AgCl is used as a precursor, the Ag–AgCl1–xBrx preserves its morphological features when x ≤ 0.5, while a morphology distortion is observed when x ≥ 0.75. Fascinatingly, although the bandgap of thus-constructed Ag–AgCl1–xBrx also exhibits a monotonic narrowing with the increase of x, they (x ≠ 0, 1) display enhanced catalytic activity compared with the two terminal materials, Ag–AgCl and Ag–AgBr, wherein Ag–AgCl0.5Br0.5, with a cube-like morphology, shows the highest catalytic performance. The synergistic effect of morphology selection and bandgap narrowing plays an important role for these intriguing new findings. Our work provides a unique forum for an optimized selection of SS-based photocatalysts in terms of morphology selection and bandgap-tuning.
Co-reporter:MingShan Zhu;MingHua Liu
Science Bulletin 2013 Volume 58( Issue 1) pp:84-91
Publication Date(Web):2013 January
DOI:10.1007/s11434-012-5367-9
An efficient visible-light-driven plasmonic photocatalyst with regard to graphene oxide (GO) hybridized Ag/Ag3PO4 (Ag/Ag3PO4/GO) nanostructures has been facilely synthesized via a deposition-precipitation method. The synthesized nanostructures have been characterized by means of scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), UV-vis spectra, Fourier transform infrared spectra (FT-IR), X-ray photoelectron spectroscopy (XPS), and Raman spectra. It has been disclosed that compared with the bare Ag/Ag3PO4 nanospecies, the GO hybridized nanostructures display enhanced photocatalytic activity for the photodegradation of methyl orange pollutant under visible-light irradiation. It is suggested that the reinforced charge transfer and the suppressed recombination of electron-hole pairs in Ag/Ag3PO4/GO, the smaller size of Ag/Ag3PO4 nanospecies in Ag/Ag3PO4/GO, all of which are the consequences of the hybridization of GO, are responsible for the enhanced photocatalytic performance. The investigation might open up new opportunities to obtain highly efficient Ag3PO4-based visible-light-driven plasmonic photocatalyst for the photodegradation of organic pollutants.
Co-reporter:Mingshan Zhu, Penglei Chen, and Minghua Liu
Langmuir 2013 Volume 29(Issue 29) pp:9259-9268
Publication Date(Web):July 2, 2013
DOI:10.1021/la401473t
We report herein that Ag/AgCl-based plasmonic photocatalysts with controlled size and shape could be easily formulated by a one-pot approach via a precipitation reaction between AgNO3 or Ag(NH3)2NO3 and NaCl. It is found that near-spherical and cube-like Ag/AgCl nanoarchitectures of 500 nm could be fabricated at lower and higher temperature, respectively. Fascinatingly, when graphene oxide (GO) nanosheets are introduced into the synthesis medium, the size of the formulated near-spherical and cube-like nanostructures, Ag/AgCl/GO, could be 2.5 and 5 times reduced to ca. 200 and 100 nm, respectively, when AgNO3 and Ag(NH3)2NO3 are employed as the silver source. The series of our Ag/AgCl-based nanostructures could be used as visible-light-driven plasmonic photocatalysts for the photodegradation of methyl orange pollutants, wherein the cube-like Ag/AgCl/GO nanoarchitectures of 100 nm display the highest catalytic activity. It is disclosed that the synergistic effect of size, shape, and GO nanosheets plays an important role for their boosted photocatalytic performances. The investigation reveals that GO nanosheets work not only as a capping agent for a controllable fabrication of Ag/AgCl nanostructures, but also as catalyst promoter during the photocatalytic performances, leading to an enhanced catalytic activity. Our unique GO-assisted method likely paves a facile avenue and initiates new opportunities for the exploration of GO-hybridized high-performance catalysts.
Co-reporter:Mingshan Zhu, Penglei Chen and Minghua Liu
Journal of Materials Chemistry A 2012 vol. 22(Issue 40) pp:21487-21494
Publication Date(Web):24 Aug 2012
DOI:10.1039/C2JM34938H
In this paper, we report that one-dimensional (1D) Ag/AgCl nanostructures could be facilely fabricated by means of an oxidation-chloridization process, wherein prefabricated 1D Ag nanowires are employed as a template. Graphene oxide (GO)-hybridized 1D Ag/AgCl nanocomposites, Ag/AgCl/GO, could also be easily formulated when GO nanosheets are involved during the oxidation-chloridization procedure. We find that compared with the parent plain 1D Ag nanowires, commercially available P25-TiO2, and spherical Ag/AgCl nanospecies, the as-produced 1D Ag/AgCl nanostructures could be used as high-performance visible-light-driven plasmonic photocatalysts for the photodegradation of organic pollutants. Moreover, the 1D Ag/AgCl/GO nanocomposites exhibit enhanced photocatalytic activity compared with the corresponding 1D Ag/AgCl nanostructures. Our experimental facts indicate that the cooperative or synergistic effects between the intrinsic morphological features of the 1D nanostructures, which facilitates an efficient directional electron transport and suppresses the scattering of the free electrons, and the advantages brought out by GO nanosheets, which favors a nice adsorption of methyl orange (MO) molecules and an efficient charge separation, conjointly contribute to the enhanced photocatalytic performance of the 1D Ag/AgCl/GO nanocomposites. This work might initiate new and more varied opportunities for the development of visible-light-driven high-performance plasmonic photocatalysts for the photodegradation of organic pollutants.
Co-reporter:Peipei Guo, Penglei Chen, Wanhong Ma and Minghua Liu
Journal of Materials Chemistry A 2012 vol. 22(Issue 38) pp:20243-20249
Publication Date(Web):25 Jun 2012
DOI:10.1039/C2JM33253A
In this paper, we have studied the supramolecular photocatalytic performance of porphyrin-based nanofibers and nanospheres in terms of photodegradation of rhodamine B (RhB) pollutant under visible light irradiation, wherein interesting morphology-dependent photocatalytic activity has been achieved. We have demonstrated that nanofibers, which are synthesized by means of surfactant-assisted self-assembly of zinc 5,10,15,20-tetra(4-pyridyl)-21H,23H-porphine (ZnTPyP), display distinct photocatalytic activity for the photodegradation of RhB molecules, where the bleaching reaction could be repeatedly operated 8 times. When the spherical nanostructures are employed, however, only negligible photocatalytic activity could be observed. The electron paramagnetic resonance investigations have revealed that singlet oxygen species are generated when spherical ZnTPyP nanostructures are employed, whereas hydroxyl radical species are produced in the nanofiber system. An electron transfer process is suggested to be responsible for the photocatalytic performance of the fibrous nanoassemblies. It is revealed that the monomeric state of ZnTPyP in the spherical nanostructures disfavors the electron transfer process, resulting in negligible photocatalytic activity. On the contrary, the formation of J-aggregates in the nanofibers facilitates the electron transfer process, resulting in distinct photocatalytic performance. The investigation suggests that an artificial supramolecular nanoantenna system based on nanostructured porphyrin assemblies could be achieved by tuning the molecular arrangement of the nanoassemblies.
Co-reporter:Mingshan Zhu, Penglei Chen, Wanhong Ma, Bin Lei, and Minghua Liu
ACS Applied Materials & Interfaces 2012 Volume 4(Issue 11) pp:6386
Publication Date(Web):November 8, 2012
DOI:10.1021/am302100u
In this paper, we report that cube-like Ag/AgCl nanostructures could be facilely fabricated in a one-pot manner through a direct-precipitation protocol under ambient conditions, wherein no additional issues such as external energy (e.g., high temperature or high pressure), surfactants, or reducing agents are required. In terms of using sodium chloride (NaCl) as chlorine source and silver acetate (CH3COOAg) as silver source, it is disclosed that simply by adding an aqueous solution of NaCl into an aqueous solution of CH3COOAg, Ag/AgCl nanostructures with a cube-like geometry, could be successfully formulated. We show that thus-formulated cube-like Ag/AgCl nanospecies could be used as high-performance yet durable visible-light-driven or sunlight-driven plasmonic photocatalysts for the photodegradation of methyl orange (MO) and 4-chlorophenol (4–CP) pollutants. Compared with the commercially available P25–TiO2, and the Ag/AgCl nanospheres previously fabricated via a surfactant-assisted method, our current cube-like Ag/AgCl nanostructures could exhibit much higher photocatalytic performance. Our template free protocol might open up new and varied opportunities for an easy synthesis of cube-like Ag/AgCl-based high-performance sunlight-driven plasmonic photocatalysts for organic pollutant elimination.Keywords: cube-like nanostucture; direct-precipitation; photodegradation; plasmonic photocatalyst; silver/silver chloride; visible-light or sunlight;
Co-reporter:Peipei Guo, Penglei Chen, and Minghua Liu
Langmuir 2012 Volume 28(Issue 44) pp:15482-15490
Publication Date(Web):October 16, 2012
DOI:10.1021/la3033594
In this paper, we report that a porphyrin, zinc 5,10,15,20-tetra(4-pyridyl)-21H,23H-porphine (ZnTPyP), could be organized to form one-dimensional (1D) nanofibers via a surfactant-assisted self-assembly (SAS) method. We disclose that when a chloroform solution of ZnTPyP is dropwise added into an aqueous solution of cetyltrimethylammonium bromide (CTAB), spherical nanostructures are formed at the initial stage. The nanospheres are naturally transformed into 1D nanostructures simply by aging under ambient conditions. Interestingly, by adjusting the volume of the employed ZnTPyP chloroform solution, the length of thus-produced 1D nanoarchitectures could be efficiently controlled. It is disclosed that longer nanofibers could be manufactured when a small volume of chloroform solution of ZnTPyP is involved, while shorter 1D nanospecies could be produced when a large volume of chloroform solution of ZnTPyP is employed. The 1D nanostructures are characterized by UV–visible spectra, scanning electron microscopy, low-resolution transmission electron microscopy, high-resolution transmission electron microscopy, and fast Fourier transformation. A solubility experiment has been carried out to disclose the dispersibility of our ZnTPyP in plain water and in CTAB aqueous solution. On the basis of the experimental facts, an explanation is proposed for these interesting new findings. The investigation provides new opportunities for the controllable assembly of porphyrin-based 1D nanomaterials with tunable length, and it sheds new scientific insights on the molecular assembly process occurring in the SAS system, wherein an oil/water system is used as the assembly medium.
Co-reporter:Yunlong Rong, Penglei Chen, Dongjun Wang, and Minghua Liu
Langmuir 2012 Volume 28(Issue 15) pp:6356-6363
Publication Date(Web):March 24, 2012
DOI:10.1021/la3005294
Molecular assemblies of two achiral porphyrins with different substituents, 5-(4-methoxycarbonylphenyl)-10,15,20-triphenyl-21H,23H-porphine (TPPCOOMe) and 5-(4-carboxyphenyl)-10,15,20-triphenyl-21H,23H-porphine (TPPCOOH), have been fabricated by the Langmuir–Blodgett (LB) technique. It is disclosed that although only slight differences exist in the molecular skeleton of these two compounds, their interfacial assemblies display distinct chiroptical properties. It is found that weak circular dichroism (CD) signals are observed from the TPPCOOH assemblies, while in the case of the TPPCOOMe assemblies, only negligible CD signals could be detected. Interestingly, after the assemblies are subjected to a thermal annealing treatment, TPPCOOH assemblies show a distinct amplification of CD signals, while those of TPPCOOMe do not. An explanation in terms of the effect of substituents on the spreading properties of the compounds and the effect of intermolecular hydrogen bonds on the cooperative stacking of the building blocks is proposed to explain these new findings. The investigation suggests that in the present porphyrin systems, besides a nice spreading property, the cooperative interaction of various noncovalent interactions, including hydrogen bonding, π–π stacking, and hydrophobic interactions, is essentially required for the occurrence of symmetry breaking at the air/water interface.
Co-reporter:Mingshan Zhu, Penglei Chen, and Minghua Liu
Langmuir 2012 Volume 28(Issue 7) pp:3385-3390
Publication Date(Web):January 20, 2012
DOI:10.1021/la204452p
In this article, we report that Ag/AgBr nanostructures and the corresponding graphene oxide (GO) hybridized nanocomposite, Ag/AgBr/GO, could be facilely synthesized by means of a surfactant-assisted assembly protocol, where an oil/water microemulsion is used as the synthesis medium. We show that thus-produced nanomaterials could be used as highly efficient and stable plasmonic photocatalysts for the photodegradation of methyl orange (MO) pollutant under sunlight irradiation. Compared with the bare Ag/AgBr nanospecies, Ag/AgBr/GO displays distinctly enhanced photocatalytic activity. More importantly, the as-prepared nanostructures exhibit higher photocatalytic activity than that of the corresponding Ag/AgBr-based nanomaterials synthesized viaa water/oil microemulsion and than that of the corresponding Ag/AgCl-based nanospecies synthesized by an oil/water microemulsion. An explanation has been proposed for these interesting findings. Our results suggest that thus-manufactured Ag/AgBr/GO plasmonic photocatalysts are promising alternatives to the traditional UV light or visible-light driven photocatalysts.
Co-reporter:Mingshan Zhu, Penglei Chen and Minghua Liu
Journal of Materials Chemistry A 2011 vol. 21(Issue 41) pp:16413-16419
Publication Date(Web):23 Sep 2011
DOI:10.1039/C1JM13326H
Herein, we have demonstrated that spherical and quasi-cubic Ag/AgCl-based plasmonic photocatalysts could be controllably synthesized by means of a one-pot surfactant-assisted method, wherein an oil-in-water system is employed as synthesis medium. We have found that thus-produced nanostructures can display stable photocatalytic performance for the photodegradation of Methyl Orange (MO) pollutant when energized with sunlight or visible light, where morphology dependent and enhanced photocatalytic activity could be realized. Compared with the Ag/AgCl nanospheres, their quasi-cubic counterparts exhibit much higher photocatalytic activity, which could be further enhanced upon hybridization with graphene oxide (GO). Moreover, in contrast to the spherical Ag/AgCl nanospecies formulated via a water-in-oil medium, those synthesized through the oil-in-water system display higher photocatalytic activity. On the basis of our experimental facts, a plausible explanation has been proposed for these significant findings. The investigation has not only one-pot controllably produced sunlight energized Ag/AgCl-based plasmonic photocatalysts with morphology dependent catalytic performance, but also essentially increased their catalytic activity.
Co-reporter:Mingshan Zhu, Penglei Chen, and Minghua Liu
ACS Nano 2011 Volume 5(Issue 6) pp:4529
Publication Date(Web):April 27, 2011
DOI:10.1021/nn200088x
In this paper, we have reported that well-defined graphene oxide (GO) enwrapped Ag/AgX (X = Br, Cl) nanocomposites, which are composed of Ag/AgX nanoparticles and gauze-like GO nanosheets, could be facilely fabricated via a water/oil system. We have shown that thus-synthesized GO-based hybrid nanocomposites could be used as a stable plasmonic photocatalyst for the photodegradation of methyl orange (MO) pollutant under visible-light irradiation. Compared with the corresponding bare Ag/AgX nanospecies, the GO-involved nanocomposites (Ag/AgX/GO) display distinctly enhanced photocatalytic activities. The hybridization of Ag/AgX with GO nanosheets causes the nice adsorptive capacity of Ag/AgX/GO to MO molecules, the smaller size of the Ag/AgX nanoparticles in Ag/AgX/GO, the facilitated charge transfer, and the suppressed recombination of electron–hole pairs in Ag/AgX/GO. It is suggested that these multifactors, resulting from the hybridization of GO, contribute to the enhanced photocatalytic performance observed from Ag/AgX/GO. The investigation likely opens up new possibilities for the development of original yet highly efficient and stable GO-based plasmonic photocatalysts that utilize visible light as an energy source.Keywords: graphene oxide; hybrid nanocomposite; silver halide; visible-light plasmonic photocatalyst; water/oil system
Co-reporter:Pingping Yao;Lang Jiang;Huaping Zhao;Hongfei Zhu;Ding Zhou;Wenping Hu;Bao-Hang Han;Minghua Liu
Advanced Materials 2010 Volume 22( Issue 44) pp:5008-5012
Publication Date(Web):
DOI:10.1002/adma.201002312
Co-reporter:Yunfeng Qiu ; Penglei Chen ;Minghua Liu
Journal of the American Chemical Society 2010 Volume 132(Issue 28) pp:9644-9652
Publication Date(Web):June 28, 2010
DOI:10.1021/ja1001967
We have shown that various porphyrin-containing nanostructures can be easily synthesized by a surfactant-assisted self-assembly (SAS) method, where an oil/aqueous medium is employed. When a chloroform solution of zinc 5,10,15,20-tetra(4-pyridyl)-21H,23H-porphine (ZnTPyP) was added dropwise into cetyltrimethylammonium bromide (CTAB) aqueous solution, diverse ZnTPyP-based nanostructures, including hollow nanospheres, solid nanospheres, nanotubes, nanorods, and nanofibers, were successfully assembled. Depending on the aging time, when a low-concentration CTAB aqueous solution was employed, hollow nanospheres or nanotubes were produced. In contrast, either solid nanospheres or nanorods were obtained by using a CTAB aqueous solution in moderate concentration. Moreover, solid nanospheres or nanofibers were produced, when a high-concentration CTAB aqueous solution was used. We have further shown that the nanorods can be hierarchically organized into a regular nanoarray on silicon substrates over a large area, while the other nanostructures cannot. Interestingly, the nanorods displayed distinct supramolecular chirality although the employed ZnTPyP is achiral. On the basis of the information obtained from scanning electron microscopy, high-resolution transmission electron microscopy, fast Fourier transformation, energy-dispersive X-ray spectroscopy, X-ray diffraction, and UV−vis and circular dichroism spectra, a tentative explanation has been proposed. Our investigation suggests that the SAS method via an oil/aqueous medium is an efficient way to synthesize organic nanostructures in a controlled manner, and that such nanostructures can show different chiroptical and assembly properties.
Co-reporter:Yunfeng Qiu, Penglei Chen, and Minghua Liu
Langmuir 2010 Volume 26(Issue 19) pp:15272-15277
Publication Date(Web):September 8, 2010
DOI:10.1021/la101959r
Interfacial molecular assemblies of eight atypical amphiphilic porphyrins, substituted with hydrophobic or hydrophilic substituents but without long alkyl chains on their molecular skeletons, have been investigated in terms of supramolecular chiralty generation and amplification. It is found that all of the originally organized interfacial molecular assemblies display very weak or undetectable supramolecular chirality. Interestingly, for those porphyrins bearing hydrophilic substituents, it is found that their molecular assemblies display distinct supramolecular chirality when applying a thermal annealing treatment. In contrast, for those bearing hydrophobic substituents, the formed assemblies remain achiral after similar treatment. This investigation suggests that the hydrophobicity/hydrophilicity of the substituents of the atypical amphiphilies could affect the occurrence of the interfacial mirror symmetry breaking substantially. It discloses that, although some of the interfacial assemblies are superficially achiral, a thermal annealing treatment could endow them with evident supramolecular chirality.
Co-reporter:Pingping Yao;Yunfeng Qiu Dr. Dr.;Yanping Ma Dr.;Shenggui He Dr.;Jian-Yu Zheng Dr.;Minghua Liu Dr.
ChemPhysChem 2010 Volume 11( Issue 3) pp:722-729
Publication Date(Web):
DOI:10.1002/cphc.200900831
Abstract
Molecular assemblies of metalloporphyrins trans-dichloro(5,10,15,20-tetra-p-tolylporphyrinato)tin(IV) (SnCl2TPPMe) and trans-dihydroxo(5,10,15,20-tetra-p-tolylporphyrinato)tin(IV) (Sn(OH)2TPPMe), which have two trans axial ligands, as well 5,10,15,20-tetrakis(4-methoxyphenyl)-21H,23H-porphine iron(III) chloride (FeClTPPOMe) and 5,10,15,20-tetraphenyl-21H,23H-porphine manganese(III) chloride (MnClTPP), which have one axial ligand, are interfacially organized by Langmuir and Langmuir–Blodgett (LB) techniques. SnCl2TPPMe and Sn(OH)2TPPMe form nanofibrous structures which can display distinct supramolecular chirality, although the molecular units themselves are achiral, while FeClTPPOMe and MnClTPP form irregular nanoparticles that display negligible supramolecular chirality. An interpretation in terms of the effects of the axial ligands is proposed for this interesting phenomenon. Moreover, compared with assemblies of the diprotonated free-base porphyrins, which are fabricated by interfacial (air/2.4 M HCl) organization of free-base porphyrin, those of SnCl2TPPMe and Sn(OH)2TPPMe display higher stability in terms of supramolecular chirality. These results indicate that the assembly properties of metalloporphyrins can essentially be affected by the axial ligands that are attached to their chromophores, and that stable chiral porphyrin supramolecular associations can be easily produced by using achiral metalloporphyrins bearing two trans axial ligands.
Co-reporter:Yiqun Zhang, Penglei Chen, Yanping Ma, Shenggui He and Minghua Liu
ACS Applied Materials & Interfaces 2009 Volume 1(Issue 9) pp:2036
Publication Date(Web):September 2, 2009
DOI:10.1021/am900399w
The interfacial diprotonation and assemblies of a free-base achiral porphyrin, 5,10,15,20-tetrakis(3,5-dimethoxyphenyl)-21H,23H-porphine, on various acidic subphases were investigated. It has been shown that the compound could be diprotonated in situ on an acidic subphase and can form assemblies. The interfacially organized supramolecular assemblies were transferred onto a solid substrate, and the assemblies showed supramolecular chirality. Interestingly, the supramolecular chirality of the assemblies of the diprotonated species showed a counterion-dependent behavior. For the assemblies fabricated from the aqueous HCl subphases, a strong Cotton effect (CE) could be observed, although the porphyrin itself is achiral. When an aqueous HBr solution was used as the subphase, the assemblies showed a weak CE, whereas no CE could be detected for the assemblies formulated from the HNO3 or HI subphase. Interestingly, when a mixture of HBr and NaCl, or HNO3 and NaCl, was employed as the subphase, the formed assemblies displayed chiral features similar to those fabricated on the HCl subphase, suggesting that the Cl− could be preferentially visualized in terms of supramolecular chirality, although the system itself is composed of achiral species. On the basis of the experimental facts and a theoretical calculation, an explanation with regard to the different sizes of the counterions and the distinct binding affinities of the counteranions to the diprotonated porphyrin species has been proposed. Our findings provide new insights into the assembly of the diprotonated porphyrins as well as the interfacially occurring symmetry breaking.Keywords: counterion; diprotonation; interfacial assembly; porphyrinoids; supramolecular chirality; symmetry breaking
Co-reporter:Pingping Yao, Haifeng Wang, Penglei Chen, Xiaowei Zhan, Xun Kuang, Daoben Zhu and Minghua Liu
Langmuir 2009 Volume 25(Issue 12) pp:6633-6636
Publication Date(Web):May 21, 2009
DOI:10.1021/la901435s
An achiral π-conjugated fluorinated fused pyrazine derivative has been spread at the air/water interface, and its assembling property is investigated. It has been found that the compound, although without any long alkyl chain, could be spread as a floating film on water surface, the surface pressure of which can be compressed up to ca. 70 mN/m. An inflection point has been observed in the isotherm of the floating film on water surface. The atomic force microscope (AFM), scanning electron microscope (SEM) as well as the transmission electron microscope (TEM) observations revealed that the floating film first formed a multilayer structure and then was compressed into nanotubes after the inflection region as a result of the rolling of the ultrathin film. Interestingly, the rolled nanotubes show circular dichroism although the molecule itself is an achiral species, suggesting the chiral nanotube is predominantly produced on the water surface. The investigation provides an effective way to fabricate supramolecular-based organic chiral nanotubes through an interfacial supramolecular assembly process.
Co-reporter:Yiqun Zhang, Dr. ;Minghua Liu Dr.
Chemistry - A European Journal 2008 Volume 14( Issue 6) pp:1793-1803
Publication Date(Web):
DOI:10.1002/chem.200701333
Abstract
We have developed a general method to construct optically active porphyrin supramolecular assemblies by using a simple air–water interfacial assembly process. The method involved the in situ diprotonation of the free-base porphyrins at the air–water interface and subsequent assembly under compression. We showed that two intrinsically achiral water-insoluble free-base porphyrin derivatives, 2,3,7,8,12,13,17,18-octaethyl-21H,23H-porphine (H2OEP) and 5,10,15,20-tetra-p-tolyl-21H,23H-porphine (H2TPPMe), could be diprotonated when spread onto a 2.4 M hydrochloric acid solution surface, and the Langmuir–Schaefer (LS) films fabricated from the subphase exhibited strong circular dichroism (CD) absorption, whereas those fabricated from pure Milli-Q water subphase did not. The experimental data suggested that the helical stacking of the achiral porphyrin building blocks was responsible for the supramolecular chirality of the assemblies. Interestingly, such a method was successfully applied to a series of other intrinsically achiral free-base porphyrins such as 5,10,15,20-tetrakis(4-methoxyphenyl)-21H,23H-porphine (H2TPPOMe), 5,10,15,20-tetraphenyl-21H,23H-porphine (H2TPP), 5,10,15,20-tetrakis(4-(allyloxy)phenyl)-21H,23H-porphine (H2TPPOA), and 5,10,15,20-tetrakis(3,5-dimethoxyphenyl)-21H,23H-porphine (H2TPPDOMe). A possible mechanism has been proposed. The method provides a facile way to obtain optically active porphyrin supramolecular assemblies by using intrinsically achiral water-insoluble free-base porphyrin derivatives.
Co-reporter:Yunfeng Qiu, Penglei Chen and Minghua Liu
Langmuir 2008 Volume 24(Issue 14) pp:7200-7207
Publication Date(Web):June 10, 2008
DOI:10.1021/la703703e
The aggregation and supramolecular chirality of the interfacial assemblies of an achiral phthalcyanine derivative, zinc 2,3,9,10,16,17,23,24-octakis(octyloxy)-29H,31H-phthaloxyanine (ZnPc), were investigated, and a surface pressure dependent behavior was observed. It was found that ZnPc could be spread as a Langmuir film on water surface and transferred onto solid substrates by the horizontal lifting method. The compound formed mixed J- and H-aggregates in the transferred Langmuir−Blodgett (LB) films. Deconvolution of the broaden Q-band revealed three main components of the spectra, which corresponded to H- and J-aggregates and medium transition aggregates, whose relative contents could be modulated by the surface pressure at which the films were transferred. On the other hand, the transferred LB films composed of these aggregates showed Cotton effects in circular dichroism spectra when the floating film was compressed over a certain surface pressure although the compound itself was achiral. The cooperative arrangement of the macrocylic ring in a helical manner through the interfacial organization was suggested to be responsible for such optical activity in the LB films. A possible explanation based on the cooperative arrangement of the ZnPc building blocks in a helical sense stacking in the aggregates was proposed.
Co-reporter:Dan Xiao, Guangwei Geng, Penglei Chen, Tiesheng Li and Minghua Liu
Physical Chemistry Chemical Physics 2017 - vol. 19(Issue 1) pp:NaN845-845
Publication Date(Web):2016/11/28
DOI:10.1039/C6CP06948G
Silver halide-based structures have been attracting great interest as efficient visible-light-driven photocatalysts towards the photodegradation of organic pollutants, and those studies focusing on their morphology-dependent catalytic performances have received particular attention. While great advancements in this regard have been witnessed in the past few years with respect to AgCl- and AgBr-based photocatalysts, relevant explorations concerning AgI-based species are relatively rare, even though the excellent durability of AgI-based structures renders them attractive candidates for potential photocatalytic uses. By means of chemical reactions between AgNO3 and tetramethylammonium iodide (TMAI), and AgNO3 and tetrabutylammonium iodide (TBAI), we herein report that AgI structures with a sheet-like and a truncated-dodecahedron-like morphology, respectively, could be controllably synthesized via a surfactant-assisted fabrication protocol. In our synthesis systems, AgNO3 works as the silver source, while the TMAI and TBAI surfactants serve not only as an iodine source but also as a directing reagent for controllable fabrication. It has been demonstrated that our AgI structures could work as visible-light-energized photocatalysts towards the photodegradation of methyl orange. We find that compared to their sheet-like counterparts, the truncated-dodecahedron-like AgI architectures exhibit substantially boosted catalytic performances. Moreover, we disclose that our truncated-dodecahedron-like AgI-based species could display excellent photocatalytic stability, wherein their catalytic reactivity displays only trivial fluctuations under visible-light irradiation even after the photoreactions have been repeated 22 times continuously. Our work might not only introduce a facile protocol for the controllable synthesis of AgI structures but also pave an avenue for facile enhancement of their catalytic performances via morphology alterations.
Co-reporter:Yunlong Rong, Penglei Chen and Minghua Liu
Chemical Communications 2013 - vol. 49(Issue 89) pp:NaN10500-10500
Publication Date(Web):2013/09/18
DOI:10.1039/C3CC46467A
Water-soluble TPPS was found to self-assemble into long nanofibers of ambiguous chirality in organic solvents, while mirror imaged chiroptical nanorods with controlled chirality were formed when (1R,2R)-(−)- or (1S,2S)-(+)-1,2-diaminocyclohexane was involved during the self-assembly.
Co-reporter:Mingshan Zhu, Penglei Chen and Minghua Liu
Journal of Materials Chemistry A 2012 - vol. 22(Issue 40) pp:NaN21494-21494
Publication Date(Web):2012/08/24
DOI:10.1039/C2JM34938H
In this paper, we report that one-dimensional (1D) Ag/AgCl nanostructures could be facilely fabricated by means of an oxidation-chloridization process, wherein prefabricated 1D Ag nanowires are employed as a template. Graphene oxide (GO)-hybridized 1D Ag/AgCl nanocomposites, Ag/AgCl/GO, could also be easily formulated when GO nanosheets are involved during the oxidation-chloridization procedure. We find that compared with the parent plain 1D Ag nanowires, commercially available P25-TiO2, and spherical Ag/AgCl nanospecies, the as-produced 1D Ag/AgCl nanostructures could be used as high-performance visible-light-driven plasmonic photocatalysts for the photodegradation of organic pollutants. Moreover, the 1D Ag/AgCl/GO nanocomposites exhibit enhanced photocatalytic activity compared with the corresponding 1D Ag/AgCl nanostructures. Our experimental facts indicate that the cooperative or synergistic effects between the intrinsic morphological features of the 1D nanostructures, which facilitates an efficient directional electron transport and suppresses the scattering of the free electrons, and the advantages brought out by GO nanosheets, which favors a nice adsorption of methyl orange (MO) molecules and an efficient charge separation, conjointly contribute to the enhanced photocatalytic performance of the 1D Ag/AgCl/GO nanocomposites. This work might initiate new and more varied opportunities for the development of visible-light-driven high-performance plasmonic photocatalysts for the photodegradation of organic pollutants.
Co-reporter:Mingshan Zhu, Penglei Chen and Minghua Liu
Journal of Materials Chemistry A 2011 - vol. 21(Issue 41) pp:NaN16419-16419
Publication Date(Web):2011/09/23
DOI:10.1039/C1JM13326H
Herein, we have demonstrated that spherical and quasi-cubic Ag/AgCl-based plasmonic photocatalysts could be controllably synthesized by means of a one-pot surfactant-assisted method, wherein an oil-in-water system is employed as synthesis medium. We have found that thus-produced nanostructures can display stable photocatalytic performance for the photodegradation of Methyl Orange (MO) pollutant when energized with sunlight or visible light, where morphology dependent and enhanced photocatalytic activity could be realized. Compared with the Ag/AgCl nanospheres, their quasi-cubic counterparts exhibit much higher photocatalytic activity, which could be further enhanced upon hybridization with graphene oxide (GO). Moreover, in contrast to the spherical Ag/AgCl nanospecies formulated via a water-in-oil medium, those synthesized through the oil-in-water system display higher photocatalytic activity. On the basis of our experimental facts, a plausible explanation has been proposed for these significant findings. The investigation has not only one-pot controllably produced sunlight energized Ag/AgCl-based plasmonic photocatalysts with morphology dependent catalytic performance, but also essentially increased their catalytic activity.
Co-reporter:Xiao Zhang, Yanping Wang, Penglei Chen, Yunlong Rong and Minghua Liu
Physical Chemistry Chemical Physics 2016 - vol. 18(Issue 20) pp:NaN14029-14029
Publication Date(Web):2016/04/25
DOI:10.1039/C6CP00683C
Porphyrins are considered to be important scaffolds bridging supramolecular chemistry and chiral chemistry, where chirality selection via physical effects such as directional stirring and spin-coating has aroused particular interest. Nevertheless, these protocols could only work on a limited number of achiral porphyrins. It still remains a formidable challenge to pave a general avenue for the construction of chiral assemblies using achiral porphyrins. By means of a unique Langmuir–Schaefer (LS) technique of a unidirectional compression configuration, we herein have demonstrated that a series of achiral porphyrins could be facilely organized to form chiral interfacial assemblies of controlled supramolecular chirality. It has been disclosed that such a fascinating chirality selection scenario is intimately related to the direction of the compression-generated vortex-like flow, while the compression speed, one of the most significant parameters of the Langmuir technique, contributes less to this issue. With regard to a surface-pressure-dependent chirality selection phenomenon, it is suggested that the directional vortex-like flow generated by lateral compression might play a role in promoting the preferential growth of chiral assemblies showing an enhanced yet controlled CD signal. Our protocol might be, to some extent, a general method for achieving chiral porphyrin assemblies of controlled chirality.
Co-reporter:Mingshan Zhu, Xiaodong Xie, Yunlong Guo, Penglei Chen, Xiaowei Ou, Gui Yu and Minghua Liu
Physical Chemistry Chemical Physics 2013 - vol. 15(Issue 48) pp:NaN21000-21000
Publication Date(Web):2013/10/14
DOI:10.1039/C3CP53383B
As the youngest in the graphene family, fluorographene has received numerous expectations from the scientific community. Investigation of fluorographene is similar to graphene and graphene oxide, wherein fabrication is an importance subject in the infancy stage. Fluorographene produced by the currently existing protocols, however, could only disperse in a limited number of solvents, and the dispersions generally exhibit short-term stability, restricting its manipulation and processing. To address this formidable challenge, we herein report that fluorographene nanosheets, most of which have a single-layered structure, could be easily formulated from commercially available graphite fluoride via a one-pot chloroform-mediated sonochemical exfoliation under ambient conditions without any pretreatment, special protection or stabilizers. Significantly, owing to the exceptional volatility of chloroform, our fluorographene originally dispersed in chloroform, could be facilely transferred into other 24 kinds of solvents via a volatilization–redispersion process, wherein dispersions of extremely long-term stability (more than six months) could be obtained. As an example to demonstrate the merit of the as-formulated fluorographene and its potential application possibilities, we further show that our fluorographene could be easily assembled as a modified layer in pentacene-based organic field-effect transistors simply by a spin-coating method, wherein distinctly increased mobility and positively shifted threshold voltage could be achieved. Considering the excellent popularity of chloroform in the scientific community, the remarkable volatility of chloroform, the broad solvent dispersibility of our fluorographene, and together with the long-term stability of the dispersions, our chloroform-mediated sonochemical exfoliation protocol likely endow fluorographene with new and broad opportunities for fabrication of graphene-based advanced functional films and nanocomposites via liquid-phase manipulation or solution-processing strategies.
Co-reporter:Mingshan Zhu, Chuncheng Chen, Penglei Chen, Bin Lei, Wanhong Ma and Minghua Liu
Physical Chemistry Chemical Physics 2013 - vol. 15(Issue 30) pp:NaN12716-12716
Publication Date(Web):2013/05/21
DOI:10.1039/C3CP51707A
The solid solution (SS) method is an effective way to design impactful photocatalysts, owing to its merit of continuous bandgap-tuning. A calcination, usually breaking the morphology of a material, has to be used to synthesize such catalysts, although the morphology is a critical issue affecting its catalytic behavior. It thus is strongly desired to construct SS-based catalysts with a shaped morphology. Here, we report that AgCl1–xBrx SS-based photocatalysts, Ag–AgCl1–xBrx, with a shaped morphology, can be produced via an ion-exchange between nanostructured Ag–AgCl and KBr. It is found that when sphere-like Ag–AgCl is employed as a precursor, the Ag–AgCl1–xBrx, maintains its morphology when x is in the range of 0–1. The bandgap, and the catalytic activities of these Ag–AgCl1–xBrx for the degradation of methyl orange, display a monotonic narrowing and a continuous enhancement, respectively, with the increase of x. In contrast, when cube-like Ag–AgCl is used as a precursor, the Ag–AgCl1–xBrx preserves its morphological features when x ≤ 0.5, while a morphology distortion is observed when x ≥ 0.75. Fascinatingly, although the bandgap of thus-constructed Ag–AgCl1–xBrx also exhibits a monotonic narrowing with the increase of x, they (x ≠ 0, 1) display enhanced catalytic activity compared with the two terminal materials, Ag–AgCl and Ag–AgBr, wherein Ag–AgCl0.5Br0.5, with a cube-like morphology, shows the highest catalytic performance. The synergistic effect of morphology selection and bandgap narrowing plays an important role for these intriguing new findings. Our work provides a unique forum for an optimized selection of SS-based photocatalysts in terms of morphology selection and bandgap-tuning.
Co-reporter:Yanping Wang, Penglei Chen, Yunfan Shen, Chuncheng Chen, Changchun Yang and Minghua Liu
Physical Chemistry Chemical Physics 2015 - vol. 17(Issue 38) pp:NaN25190-25190
Publication Date(Web):2015/08/24
DOI:10.1039/C5CP03618F
Ag/AgCl-based plasmonic photocatalysts have received much attention as emerging visible-light-driven photocatalysts, wherein those characterized by 1D morphology have aroused great expectations. Most of the current existing protocols for the fabrication of 1D materials, however, suffer from either multistep tedious synthesis processes or the requirement of rigorous experimental conditions. A one-pot fabrication method feasible under ambient conditions is strongly desired. By means of a surfactant-assisted protocol, we report herein that Ag/AgCl structures of near-spherical and 1D morphology could be controllably produced. We show that near-spherical Ag/AgCl species could be produced immediately after dropping an AgNO3 aqueous solution into an aqueous solution of cetyltrimethylammonium chloride (CTAC) surfactant under stirring. Interestingly, we show that these initially formed near-spherical species could automatically evolve into 1D Ag/AgCl fibers simply by extending the stirring time under ambient conditions. In our new protocol, CTAC works not only as a chlorine source but also as a directing reagent to assist the formation of 1D Ag/AgCl structures. Moreover, we demonstrate that compared to near-spherical structures, our Ag/AgCl fibers could display boosted catalytic performances towards the photodegradation of the methyl orange pollutant under visible light irradiation. Our work might launch an easy method for the construction of fibrous Ag/AgCl architectures of superior photocatalytic reactivity, and it also provides deep insights into the surfactant-assisted synthesis.
Co-reporter:Xiao Zhang, Mingshan Zhu, Penglei Chen, Yongjun Li, Huibiao Liu, Yuliang Li and Minghua Liu
Physical Chemistry Chemical Physics 2015 - vol. 17(Issue 2) pp:NaN1225-1225
Publication Date(Web):2014/11/14
DOI:10.1039/C4CP04683H
Advanced functional hybrids based on carbon materials (CMs) represent one of the main achievements of scientific communities. To achieve the hybridization, pristine CMs have to be chemically modified, or surfactants, which are nonfunctional for the performances of the hybrids, have to be employed as a cross-linkage. The construction of pristine CM-based hybrids using dual-functional coupling reagents, which work not only as a glue for hybridization but also as a functional component for enhanced performance, is strongly desired. Here, we report that pristine graphdiyne (GD), a recently synthesized new carbon allotrope, can be facilely hybridized with Ag/AgBr using graphene oxide (GO) as a cross-linkage. We demonstrate that compared to Ag/AgBr, Ag/AgBr/GO, and Ag/AgBr/GD, our Ag/AgBr/GO/GD exhibits an enhanced photocatalytic performance toward the degradation of methyl orange (MO) pollutant under visible light irradiation. In our Ag/AgBr/GO/GD, GO serves not only as a glue for a successful hybridization, but also as a functional component for enhanced catalytic performance. Beyond GD, our work likely paves a new avenue for the fabrication of advanced functional hybrids based on pristine carbon allotropes, wherein desired functions or properties might be achieved by choosing desired CMs and desired hybridized components.
Co-reporter:Peipei Guo, Penglei Chen, Wanhong Ma and Minghua Liu
Journal of Materials Chemistry A 2012 - vol. 22(Issue 38) pp:NaN20249-20249
Publication Date(Web):2012/06/25
DOI:10.1039/C2JM33253A
In this paper, we have studied the supramolecular photocatalytic performance of porphyrin-based nanofibers and nanospheres in terms of photodegradation of rhodamine B (RhB) pollutant under visible light irradiation, wherein interesting morphology-dependent photocatalytic activity has been achieved. We have demonstrated that nanofibers, which are synthesized by means of surfactant-assisted self-assembly of zinc 5,10,15,20-tetra(4-pyridyl)-21H,23H-porphine (ZnTPyP), display distinct photocatalytic activity for the photodegradation of RhB molecules, where the bleaching reaction could be repeatedly operated 8 times. When the spherical nanostructures are employed, however, only negligible photocatalytic activity could be observed. The electron paramagnetic resonance investigations have revealed that singlet oxygen species are generated when spherical ZnTPyP nanostructures are employed, whereas hydroxyl radical species are produced in the nanofiber system. An electron transfer process is suggested to be responsible for the photocatalytic performance of the fibrous nanoassemblies. It is revealed that the monomeric state of ZnTPyP in the spherical nanostructures disfavors the electron transfer process, resulting in negligible photocatalytic activity. On the contrary, the formation of J-aggregates in the nanofibers facilitates the electron transfer process, resulting in distinct photocatalytic performance. The investigation suggests that an artificial supramolecular nanoantenna system based on nanostructured porphyrin assemblies could be achieved by tuning the molecular arrangement of the nanoassemblies.
Co-reporter:Liping Wang, Xiaodong Xie, Weifeng Zhang, Ji Zhang, Mingshan Zhu, Yunlong Guo, Penglei Chen, Minghua Liu and Gui Yu
Journal of Materials Chemistry A 2014 - vol. 2(Issue 32) pp:NaN6490-6490
Publication Date(Web):2014/07/03
DOI:10.1039/C4TC00251B
High-performance organic phototransistors (OPTs) have been successfully constructed using bitriisopropylsilylethynyl tetraceno[2,3-b]thiophenes (TIPSEthiotet) or pentacene as a semiconductor layer. Fluorographene (FG) nanosheets were used to modify the interface between an organic semiconductor layer and gate dielectric. The effects of interface modification were investigated. It was found that enhanced photoresponsivity and a boosted photocurrent/dark-current ratio could be easily achieved after the implantation of modification layers. The constructed FG-modified devices based on TIPSEthiotet showed a maximum photoresponsivity of 21.83 A W−1 and a photocurrent/dark-current ratio of 1.85 × 106 under white light irradiation. Meanwhile, for the FG-modified OPT device based on pentacene, a high photoresponsivity of 144 A W−1 was obtained under white light irradiation with an optical power of as low as 25 μW cm−2. This photoresponsivity datum is higher than that of most OPTs based on pentacene reported under the same conditions. In addition, the mobilities of the devices could also be increased distinctly after the introduction of the FG-modified layer. The experimental facts indicate that the strong electron trapping ability of the fluorine atoms in the FG nanosheets and the well-known photovoltaic effect play an important role in these interesting results.
Co-reporter:Congcong Zhang, Penglei Chen and Wenping Hu
Chemical Society Reviews 2015 - vol. 44(Issue 8) pp:NaN2107-2107
Publication Date(Web):2015/03/02
DOI:10.1039/C4CS00326H
Organic field-effect transistors (OFETs) are one of the key components of modern organic electronics. While the past several decades have witnessed huge successes in high-performance OFETs, their sophisticated functionalization with regard to the responses towards external stimulations has also aroused increasing attention and become an important field of general concern. This is promoted by the inherent merits of organic semiconductors, including considerable variety in molecular design, low cost, light weight, mechanical flexibility, and solution processability, as well as by the intrinsic advantages of OFETs including multiparameter accessibility and ease of large-scale manufacturing, which provide OFETs with great potential as portable yet reliable sensors offering high sensitivity, selectivity, and expeditious responses. With special emphases on the works achieved since 2009, this tutorial review focuses on OFET-based gas sensors. The working principles of this type of gas sensors are discussed in detail, the state-of-the-art protocols developed for high-performance gas sensing are highlighted, and the advanced gas discrimination systems in terms of sensory arrays of OFETs are also introduced. This tutorial review intends to provide readers with a deep understanding for the future design of high-quality OFET gas sensors for potential uses.
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