Co-reporter:Yanping Tang, Fan Jing, Zhixiao Xu, Fan Zhang, Yiyong Mai, and Dongqing Wu
ACS Applied Materials & Interfaces April 12, 2017 Volume 9(Issue 14) pp:12340-12340
Publication Date(Web):April 3, 2017
DOI:10.1021/acsami.6b15461
A bifunctional electrocatalyst for both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is highly attractive for the manufacture of clean energy conversion devices. In this work, highly crumpled hybrid of nitrogen and sulfur dual-doped graphene and quasi-hexagonal Co9S8 nanoplates (Co9S8/NSGg-C3N4) is fabricated via a facile ionic assembly approach. The unique structure of Co9S8/NSGg-C3N4 renders it high specific surface area (288.3 m2 g–1) and large pore volume (1.32 cm3 g–1). As the electrocatalyst for ORR, Co9S8/NSGg-C3N4 demonstrates excellent performance with the onset potential of −0.02 V vs Ag/AgCl and the limited current density of 6.05 mA cm–2 at −0.9 V vs Ag/AgCl. Co9S8/NSGg-C3N4 also presents outstanding catalytic activity toward OER by delivering a limited current density of 48 mA cm–2 at 1 V vs Ag/AgCl. The bifunctional catalytic behaviors of Co9S8/NSGg-C3N4 enable the assembly of a rechargeable Zn–air battery with it as the cathode catalyst, which exhibits stable discharge/charge voltage plateaus upon long time cycling over 50 h.Keywords: cobalt pentlandite; crumpled architecture; nitrogen and sulfur dual-doped graphene; oxygen evolution reaction; oxygen reduction reaction;
Co-reporter:Zongsheng Hou, Yeqing Jin, Xin Xi, Tao Huang, Dongqing Wu, Peimin Xu, Ruili Liu
Journal of Colloid and Interface Science 2017 Volume 488() pp:317-321
Publication Date(Web):15 February 2017
DOI:10.1016/j.jcis.2016.11.008
Nitrogen-doped graphene aerogels with hierarchically porous architectures (N-Gs) are fabricated through the co-assembly of graphene oxide and o-phthalonitrile in a solvothermal process and the thermal treatment of the obtained composites at different temperatures. The structural characterizations indicate that both mesopores and macropores exist in the monolithic N-Gs. More importantly, the architectures, porosities and compositions show obvious dependence on the thermal treatment temperature. As the metal-free catalyst for oxygen reduction reaction in basic media, the sample thermally treated at 750 °C shows the best catalytic performances among the three N-Gs, which is owing to its advantages in the surface areas and content of active N species.Nitrogen-doped graphene aerogels with hierarchically porous architectures (N-Gs) are fabricated through the co-assembly of graphene oxide and o-phthalonitrile in a solvothermal process and the thermal treatment of the obtained composites at different temperatures. The structural characterizations indicate that both mesopores and macropores exist in the monolithic N-Gs. More importantly, the architectures, porosities and compositions show obvious dependence on the thermal treatment temperature. As the metal-free catalysts for oxygen reduction reaction in basic media, the sample thermally treated at 750 °C shows the best catalytic performances among the three N-Gs, which is owing to its advantages in the surface areas and content of active N species.
Co-reporter:Yanshan Huang;Arezoo Dianat;Manferd Bobeth;Tao Huang;Yiyong Mai;Fan Zhang;Gianaurelio Cuniberti;Xinliang Feng
Journal of Materials Chemistry A 2017 vol. 5(Issue 4) pp:1588-1594
Publication Date(Web):2017/01/24
DOI:10.1039/C6TA09161J
Hierarchically porous nitrogen-doped graphene frameworks (N-GFs) are fabricated through the ice-templating of GO with polyethylenimine and the thermal treatment of the resultant hybrids. As cathode materials in lithium ion batteries (LIBs), the obtained N-GFs exhibit an outstanding specific capacity of 379 mA h g−1 at 0.5 A g−1 for 2500 cycles. Even at an ultrahigh current density of 5 A g−1, the N-GFs maintain a capacity of 94 mA h g−1, superior to that of most reported LIB cathode materials. The experimental results and quantum mechanics calculations suggest that pyridinic-like N and pyridinic N-oxide in graphene are responsible for the excellent cathodic performance of the bipolar N-GFs by providing fast surface faradaic reactions with both p- and n-doped states.
Co-reporter:Jing Cao, Tao Huang, Ruili Liu, Xin Xi, Dongqing Wu
Electrochimica Acta 2017 Volume 230(Volume 230) pp:
Publication Date(Web):10 March 2017
DOI:10.1016/j.electacta.2017.02.001
The design versatility and performance advantages render supercapacitors (SCs) the highly appealing candidates for the energy storage units in flexible devices. For this purpose, a flexible electrode with high capacitance and excellent mechanical stability is essential. Herein, the facile fabrication strategy towards flexible SC electrodes with polyaniline (PANI) nanowires loading on nitrogen-doped carbon coated SS mesh (PANI/N-C/SS) is developed via a simple hydrothermal carbonization process and the following deposition of PANI. Derived from glucose and dicyandiamide, the nitrogen-doped carbon layer can effectively improve the contract of the SS substrate and PANI. The resultant PANI/N-C/SS electrode delivers a high areal capacitance of 624 mF cm−2 at 0.05 mA cm−2. With a large size of 40 cm2, the solid-state symmetric capacitor based on PANI/N-C/SS still possesses a capacitance of 122.6 mF cm−2, corresponding to a high energy density of 0.22 mWh cm−2.
Co-reporter:Zhixiao Xu;Xiaodong Zhuang;Chongqing Yang;Jing Cao;Zhaoquan Yao;Yanping Tang;Jianzhong Jiang;Xinliang Feng
Advanced Materials 2016 Volume 28( Issue 10) pp:1981-1987
Publication Date(Web):
DOI:10.1002/adma.201505131
Co-reporter:Jieqiong Shan, Yuxin Liu, Yuezeng Su, Ping Liu, Xiaodong Zhuang, Dongqing Wu, Fan Zhang and Xinliang Feng
Journal of Materials Chemistry A 2016 vol. 4(Issue 1) pp:314-320
Publication Date(Web):17 Nov 2015
DOI:10.1039/C5TA08109B
Graphene-directed two-dimensional (2D) nitrogen-doped porous carbon frameworks (GPF) as the hosts for sulfur were constructed via the ionothermal polymerization of 1,4-dicyanobenzene directed by the polyacrylonitrile functionalized graphene nanosheets. As cathodes for lithium–sulfur (Li–S) batteries, the prepared GPF/sulfur nanocomposites exhibited a high capacity up to 962 mA h g−1 after 120 cycles at 2 A g−1. A high reversible capacity of 591 mA h g−1 was still retained even at an extremely large current density of 20 A g−1. Such impressive electrochemical performance of GPF should benefit from the 2D hierarchical porous architecture with an extremely high specific surface area, which could facilitate the efficient entrapment of sulfur and polysulfides and afford rapid charge transfer, fast electronic conduction as well as intimate contact between active materials and the electrolyte during cycling.
Co-reporter:Xia Xing, Ruili Liu, Shaoqing Liu, Suo Xiao, Yi Xu, Chi Wang, Dongqing Wu
Electrochimica Acta 2016 Volume 194() pp:310-316
Publication Date(Web):10 March 2016
DOI:10.1016/j.electacta.2016.02.096
In this work, the composites of nitrogen-doped graphene framework and Co3O4 nanoparticles with adjustable morphologies (NG/Co3O4) were fabricated via a surfactant-assisted hydrothermal route for first time. Three different surfactants including triblock copolymer F127, cetyltrimethyl ammonium bromide and sodium dodecyl sulfate are involved in the hybrid-assembly of graphene oxide, o-phthalonitrile and cobalt acetate in water/ethanol. Among the obtained samples, the one using F127 (NG/Co3O4-F127) manifests the most homogeneous distribution of Co3O4 NPs with the size of ∼ 15 nm in the macropore-walls formed by NG. As the anode material in lithium ion battery (LIB), NG/Co3O4-F127 exhibits excellent electrochemical performance, which is superior to the other composites and most of the previously reported Co3O4 based anode materials in LIBs.
Co-reporter:Chongqing Yang, Dongqing Wu, Wuxue Zhao, Weizhen Ye, Zhixiao Xu, Fan Zhang and Xinliang Feng
CrystEngComm 2016 vol. 18(Issue 6) pp:877-880
Publication Date(Web):04 Jan 2016
DOI:10.1039/C5CE02171E
A controllable self-assembly strategy of positively charged polycyclic aromatic hydrocarbons (PCPAH) towards the formation of rectangle sheets and ribbon-like nanostructures has been achieved by choosing divalent anions with different sizes. In contrast, only rod-like nanostructures are obtained from PCPAH with univalent anions. It is revealed that the divalent anions play a key role in guiding the packing of PCPAH, which provides an unprecedented route to fabricate two-dimensional nanostructures.
Co-reporter:Ruili Liu, Yeqing Jin, Peimin Xu, Xia Xing, Yuxing Yang, Dongqing Wu
Journal of Colloid and Interface Science 2016 Volume 464() pp:83-88
Publication Date(Web):15 February 2016
DOI:10.1016/j.jcis.2015.11.007
As a novel electrocatalyst for oxygen reduction reaction (ORR), nitrogen-doped graphene aerogel supported cobalt nanoparticles (Co-NGA) is archived by a hybrid-assembly of graphene oxide (GO), o-phthalonitrile and cobalt acetate and the following thermal treatment. The hybrid-assembly process successfully combines the ionic assembly of GO sheets and Co ions with the coordination between o-phthalonitrile and Co ions, which can be converted to nitrogen doped carbon and Co nanoparticles in the pyrolysis process under nitrogen flow. Remarkable features of Co-NGA including the macroporous graphene scaffolds, high surface area, and N/Co-doping effect can lead to a high catalytic efficiency for ORR. As the results, the composites pyrolyzed at 600 °C (Co-NGA600) shows excellent electrocatalytic activities and kinetics for ORR in basic media, which are comparable with those of Pt/C catalyst, together with superior durability.A novel hybrid electrocatalyst consisting of nitrogen-doped graphene aerogel supported cobalt nanoparticles (Co-NGA) is archived by a facile hybrid-assembly of graphene oxide, o-phthalonitrile and cobalt acetate and the following thermal treatment, which exhibits a high catalytic efficiency for oxygen reduction reaction in basic media.
Co-reporter:Xin Xi, Ruili Liu, Tao Huang, Yi Xu, Dongqing Wu
Journal of Colloid and Interface Science 2016 Volume 483() pp:34-40
Publication Date(Web):1 December 2016
DOI:10.1016/j.jcis.2016.08.008
To enforce the interactions between polyaniline (PANI) and graphene, a facile strategy is developed in this work to fabricate the strongly coupled hybrids of PANI nanofibers and graphene (named as PAGs) by introducing different diamines to functionalize graphene oxide. As the electrode material in a two-electrode supercapacitor (SC), the ethylenediamine-functionalized hybrid (PAG-EDA) deliveries an excellent volumetric specific capacitance of 810 F cm−3 at 5 mV s−1. The SC also manifests high cycling stability by maintaining 84.4% of the initial capacitance after 10,000 cycles. More importantly, PAG-EDA renders the SC to have both high energy density (92.15 W h kg−1) and high power density (182.28 kW kg−1), superior to most of the previously reported PANI based SC electrode materials.A facile strategy is developed in this work to fabricate the strongly coupled hybrids of polyaniline (PANI) and graphene (named as PAGs) by introducing different diamines to functionalize graphene oxide. As the electrode material in a two-electrode supercapacitor (SC), the ethylenediamine-functionalized hybrid (PAG-EDA) deliveries an excellent volumetric specific capacitance of 810 F cm−3 at 5 mV s−1. The SC also manifests high cycling stability by maintaining 84.4% of the initial capacitance after 10,000 cycles. More importantly, PAG-EDA renders the SC to have both high energy density (92.15 W h kg−1) and high power density (182.28 kW kg−1), superior to most of the previously reported PANI based SC electrode materials.
Co-reporter:Shaoqing Liu, Ruili Liu, Xia Xing, Chongqing Yang, Yi Xu and Dongqing Wu
RSC Advances 2016 vol. 6(Issue 38) pp:31884-31888
Publication Date(Web):22 Mar 2016
DOI:10.1039/C5RA26521E
A facile one-step hydrothermal strategy to fabricate nitrogen-rich carbon dots (N-rich CDs) with melamine and citric acid as the precursors has been successfully developed. The as-prepared N-rich CDs exhibit a uniform quasi-spherical morphology, high N content of about 24 wt% and very strong photoluminescence (PL) with a high quantum yield of ∼42%. Additionally, the PL emission of these N-rich CDs can be stabilized in a wide pH range from 4.0 to 11.0. More importantly, the N-rich CDs can be utilized as the label-free PL sensors for the highly selective and sensitive detection of Fe3+ ions in aqueous solution with a very low detection limit of 142 nM.
Co-reporter:Miao Chen, Chongqing Yang, Zhixiao Xu, Yanping Tang, Jianzhong Jiang, Ping Liu, Yuezeng Su and Dongqing Wu
RSC Advances 2016 vol. 6(Issue 17) pp:13666-13669
Publication Date(Web):02 Feb 2016
DOI:10.1039/C5RA26181C
A two-dimensional hybrid of naphthalene diimide and reduced graphene oxide (NDI–RGO) has been constructed by a facile self-assembly strategy. In the resulting hybrid, the non-covalent interactions between NDI and RGO enable the uniform distribution of NDI on the surface of RGO. As the cathode material in lithium ion batteries, NDI–RGO shows excellent revisable capacity and rate capability.
Co-reporter:Yanshan Huang;Yanping Tang;Dr. Yiyong Mai;Xinjing Wang;Chi Wang;Dr. Sheng Han;Dr. Fan Zhang;Dr. Dongqing Wu; Xinliang Feng
Chemistry – An Asian Journal 2016 Volume 11( Issue 8) pp:1194-1198
Publication Date(Web):
DOI:10.1002/asia.201501140
Abstract
A three-dimensional polymeric carbon nitride/graphene framework (CN/GF) was fabricated by the ionic self-assembly of graphene oxide and protonated polymeric carbon nitride nanosheets. As the cathode material in lithium-ion batteries, CN/GF showed an excellent reversible capacity of 184 mA h g−1 at 0.05 A g−1 for 150 cycles and maintained the capacity of 60 mA h g−1 at 5 A g−1.
Co-reporter:Sheng Han;Chi Wang;Yanshan Huang;Jianzhong Jiang
Journal of Materials Science 2016 Volume 51( Issue 10) pp:4856-4863
Publication Date(Web):2016 May
DOI:10.1007/s10853-016-9790-1
Three-dimensional hybrids of cobalt oxide (Co3O4) and graphene frameworks are fabricated via a facile hydrothermal self-assembly process. By adjusting the time of the hydrothermal treatment, the morphologies of the Co3O4 components can be modified from rods to nanoparticles, which further manifest influences on the electrochemical performance of the hybrids. As the anode in lithium-ion battery, the hybrid loaded with spherical Co3O4 nanoparticles exhibits the highest reversible capacity of 1148 mA h g−1 at 100 mA g−1 for 100 cycles among the three samples. Even at a high current density of 5000 mA g−1, its reversible capacity is still kept at 600 mA h g−1, outperforming the reported hybrids of Co3O4 and graphene.
Co-reporter:Ruili Liu;Li Wan;Shaoqing Liu;Lixia Pan;Dongyuan Zhao
Advanced Functional Materials 2015 Volume 25( Issue 4) pp:526-533
Publication Date(Web):
DOI:10.1002/adfm.201403280
Hierarchically porous composites with mesoporous carbon wrapping around the macroporous graphene aerogel can combine the advantages of both components and are expected to show excellent performance in electrochemical energy devices. However, the fabrication of such composites is challenging due to the lack of an effective strategy to control the porosity of the mesostructured carbon layers. Here an interface-induced co-assembly approach towards hierarchically mesoporous carbon/graphene aerogel composites, possessing interconnected macroporous graphene networks covered by highly ordered mesoporous carbon with a diameter of ≈9.6 nm, is reported. And the orientation of the mesopores (vertical or horizontal to the surface of the composites) can be tuned by the ratio of the components. As the electrodes in supercapacitors, the resulting composites demonstrate outstanding electrochemical performances. More importantly, the synthesis strategy provides an ideal platform for hierarchically porous graphene composites with potential for energy storage and conversion applications.
Co-reporter:Jieqiong Shan, Yuxin Liu, Ping Liu, Yanshan Huang, Yuezeng Su, Dongqing Wu and Xinliang Feng
Journal of Materials Chemistry A 2015 vol. 3(Issue 47) pp:24148-24154
Publication Date(Web):2015/10/28
DOI:10.1039/C5TA06617D
A dual-doping approach for nitrogen-doped carbon-coated SnO2–SnS/graphene nanosheets (N–C@SnO2–SnS/GN) has been developed, using hydrothermal carbonization of sucrose with SnO2-decorated graphene and ammonium thiocyanate and a subsequent thermal treatment. The resulting hybrid manifests a typical two-dimensional core–shell architecture, with a N-doped carbon coating over the SnS- and SnO2-decorated graphene nanosheets. Used as the anode material in lithium ion batteries (LIBs), N–C@SnO2–SnS/GN delivers a high specific capacity of 1236 mA h g−1 at a current density of 0.1 A g−1 after 110 cycles, which outperforms most state-of-the-art tin-based LIB anodes with core–shell structures.
Co-reporter:Ruili Liu, Lixia Pan, Li Wan and Dongqing Wu
Physical Chemistry Chemical Physics 2015 vol. 17(Issue 6) pp:4724-4729
Publication Date(Web):09 Jan 2015
DOI:10.1039/C4CP05211K
Nitrogen-doped mesoporous carbon microfibers (NMCMFs) were prepared via an evaporation-induced tri-consistent assembly of a triblock copolymer, resols and prehydrolyzed tetraethoxy silane on natural silk followed by pyrolysis. The resultant NMCMFs inherit the advantages of both order mesoporous carbons (OMCs) and carbon microfibers (CMFs), such as uniform meso-channels, high surface area, high nitrogen content, excellent electronic conductivity as well as good flexibility. Owing to the well-designed nanostructure and the synergistic effects of the strongly coupled components, the binder-free electrodes based on NMCMFs exhibit enhanced capacity (189 F g−1 at 5 mV s−1), excellent rate capability (107 F g−1 at 100 mV s−1) and durability (maintained over 96% of the initial capacitance after 10000 cycles) in electric double-layer capacitors, outperforming those of OMCs and CMFs derived from pristine silk.
Co-reporter:Ruili Liu, Mengping Gao, Jing Zhang, Zhilian Li, Jinyang Chen, Ping Liu and Dongqing Wu
RSC Advances 2015 vol. 5(Issue 31) pp:24205-24209
Publication Date(Web):27 Feb 2015
DOI:10.1039/C5RA00089K
A facile approach towards photoluminescent carbon dots (CDs) has been developed by the microwave-hydrothermal treatment of rice straw in the mixed solvent of water and ionic liquid (1-allyl-3-methylimidazolium chloride, AMIM-Cl). AMIM-Cl helps to dissolve the cellulose in straw and provides nitrogen atoms for the resulting heteroatom doped CDs. As a result, the straw produced CDs possess a spherical morphology and a high quantum yield of about 22.58%, which is higher than the other CDs prepared from biomass. In addition, the CDs can serve as an effective label-free fluorescent sensor for the detection of Fe(III) ions with a very low detection limit of 200 nM.
Co-reporter:Ruili Liu, Lixia Pan, Xiaoxue Liu and Dongqing Wu
RSC Advances 2015 vol. 5(Issue 22) pp:16765-16768
Publication Date(Web):19 Jan 2015
DOI:10.1039/C4RA13720E
Ordered mesoporous carbon/graphene aerogel (OMC/GA) is prepared by an evaporation-induced tri-constituent assembly route. Owing to the hierarchically porous structures and high specific surface area, the resultant OMC/GA exhibits enhanced electrochemical performance as the electrode in electrochemical capacitors.
Co-reporter:Yuxin Liu; Ping Liu; Dongqing Wu;Yanshan Huang;Yanping Tang; Yuezeng Su; Fan Zhang; Xinliang Feng
Chemistry - A European Journal 2015 Volume 21( Issue 14) pp:5617-5622
Publication Date(Web):
DOI:10.1002/chem.201406029
Abstract
Heteroatom doping is an effective method to adjust the electrochemical behavior of carbonaceous materials. In this work, boron-doped, carbon-coated SnO2/graphene hybrids (BCTGs) were fabricated by hydrothermal carbonization of sucrose in the presence of SnO2/graphene nanosheets and phenylboronic acid or boric acid as dopant source and subsequent thermal treatment. Owing to their unique 2D core–shell architecture and B-doped carbon shells, BCTGs have enhanced conductivity and extra active sites for lithium storage. With phenylboronic acid as B source, the resulting hybrid shows outstanding electrochemical performance as the anode in lithium-ion batteries with a highly stable capacity of 1165 mA h g−1 at 0.1 A g−1 after 360 cycles and an excellent rate capability of 600 mA h g−1 at 3.2 A g−1, and thus outperforms most of the previously reported SnO2-based anode materials.
Co-reporter:Yanshan Huang, Dongqing Wu, Jianzhong Jiang, Yiyong Mai, Fan Zhang, Hao Pan, Xinliang Feng
Nano Energy 2015 Volume 12() pp:287-295
Publication Date(Web):March 2015
DOI:10.1016/j.nanoen.2014.12.034
•C/SnO2/GM with highly oriented macroporous and carbon-coated structure was fabricated by ice-templating.•The novel strategy can be further extended to prepare other metal phosphate (C/FePO4/GM).•The hybrids are beneficial to their electrochemical performance as LIB anodes and cathodes.The highly oriented macroporous graphene monoliths hybridized with carbon-coated metal oxide or phosphate (C/M/GM) with core/shell structure were fabricated by an ice-templating co-assembly of M/GO nanosheets (metal oxide/phosphates decorated graphene oxide) and polyvinyl alcohol (PVA), and following thermal treatment. With either tin oxide (SnO2) or iron phosphate (FePO4), the resulting C/M/GMs possess periodic macropores with diameters ranging from 5 to 20 μm and high loading contents of active components (~70 wt%). Served as the anode in LIBs, C/SnO2/GM maintains an ultrahigh capacity of 1665 mA h g−1 at a current density of 0.2 A g−1 for 200 cycles. Even at an ultrafast charge rate of 10 A g−1, a decent capacity of 300 mA h g−1 can still be achieved, with excellent cycling stability. And C/FePO4/GM also delivers a highly reversible capacity of 175 mA h g−1 at a current density of 0.05 A g−1 for 150 cycles and a good capacity of 57 mA h g−1 at 2 A g−1 when as the LIB cathode electrode.Highly oriented macroporous graphene monoliths hybridized with carbon-coated metal oxide nanoparticles were fabricated by ice-templating assembly method, which possessed ordered macropores, and exhibited ultrahigh capacity and rate capability for lithium ion batteries.
Co-reporter:Yanping Tang, Dongqing Wu, Yiyong Mai, Hao Pan, Jing Cao, Chongqing Yang, Fan Zhang and Xinliang Feng
Nanoscale 2014 vol. 6(Issue 24) pp:14679-14685
Publication Date(Web):23 Oct 2014
DOI:10.1039/C4NR05519E
A novel 2D hybrid with MoS2 nanocrystals strongly coupled on nitrogen-enriched graphene (MoS2/NGg-C3N4) is realized by mild temperature pyrolysis (550 °C) of a self-assembled precursor (MoS3/g-C3N4–H+/GO). With rich active sites, the boosted electronic conductivity and the coupled structure, MoS2/NGg-C3N4 achieves superior lithium storage performance.
Co-reporter:Sheng Han, Jinzuan Wang, Shuang Li, Dongqing Wu and Xinliang Feng
Journal of Materials Chemistry A 2014 vol. 2(Issue 17) pp:6174-6179
Publication Date(Web):28 Nov 2013
DOI:10.1039/C3TA14585A
Three-dimensional (3D) macroporous graphene aerogel-supported Fe5(PO4)4(OH)3·2H2O (iron(III) hydroxide phosphate dihydrate) microspheres (GA/IHPDs) have been fabricated by the hydrothermal mineralization of Fe3+ and PO43− ions in the presence of graphene oxide (GO). The resulting hybrids own interconnected 3D macroporous frameworks with the IHPD particles (2 μm in diameter) encapsulated in flexible graphene sheets. Used as the cathode material in lithium ion batteries (LIBs), the GA/IHPDs hybrids show an excellent reversible specific capacity of 155 mA h g−1 after 300 cycles at a current density of 50 mA g−1 and maintain the specific capacities of 80 and 56 mA h g−1 at the ultrahigh current densities of 2000 and 5000 mA g−1, respectively. To our best knowledge, such an electrochemical performance of GA/IHPDs is superior to the literature reported graphene and other carbon based LiFePO4, or FePO4 hybrids. With a simple fabrication procedure and desirable electrochemical performance, this method offers a highly promising candidate for commercialized cathode materials of LIBs.
Co-reporter:Ruili Liu, Li Wan, Shuhua Liu, Yizhen Yu, Shuang Li, Dongqing Wu
Journal of Colloid and Interface Science 2014 Volume 414() pp:59-65
Publication Date(Web):15 January 2014
DOI:10.1016/j.jcis.2013.09.047
•Magnetic mesoporous graphitic composite (MMGC) is prepared by a co-assembly method.•It exhibits uniform pore size, high surface area and stable magnetic properties.•It shows excellent adsorption ability for the removal of contaminants in solution.Magnetic nanoparticles have been widely investigated due to their environmental and biomedical applications. However, the unavoidable problems associated with them are their intrinsic instability and the trend of the agglomeration. Mesoporous carbon is considered as an ideal matrix for the protection of magnetic nanoparticles owing to its high surface area, excellent chemical and thermal stability. The preparation of morphology defined composites of magnetic nanoparticles and mesoporous carbon is of great importance for their practical applications. In this work, magnetic mesoporous graphitic composites (MMGCs) with defined rhombododecahedral morphology are fabricated by the pyrolysis of the composites from the hierarchical co-assembly of amphiphilic triblock copolymer, resol oligomers and Fe3O4 nanoparticles. MMGCs exhibit narrow bimodal pore size distribution, high surface area and highly stable magnetic properties, which provide them excellent adsorption ability for the removal of organic contaminants in aqueous solution.Graphical abstract
Co-reporter:Yuezeng Su, Shuang Li, Dongqing Wu, Fan Zhang, Haiwei Liang, Pengfei Gao, Chong Cheng, and Xinliang Feng
ACS Nano 2012 Volume 6(Issue 9) pp:8349
Publication Date(Web):August 29, 2012
DOI:10.1021/nn303091t
Metal oxides (MOs) have been widely investigated as promising high-capacity anode material for lithium ion batteries, but they usually exhibit poor cycling stability and rate performance due to the huge volume change induced by the alloying reaction with lithium. In this article, we present a double protection strategy by fabricating a two-dimensional (2D) core–shell nanostructure to improve the electrochemical performance of metal oxides in lithium storage. The 2D core–shell architecture is constructed by confining the well-defined graphene based metal oxides nanosheets (G@MO) within carbon layers. The resulting 2D carbon-coated graphene/metal oxides nanosheets (G@MO@C) inherit the advantages of graphene, which possesses high electrical conductivity, large aspect ratio, and thin feature. Furthermore, the carbon shells can tackle the deformation of MO nanoparticles while keeping the overall electrode highly conductive and active in lithium storage. As the result, the produced G@MO@C hybrids exhibit outstanding reversible capacity and excellent rate performance for lithium storage (G@SnO2@C, 800 mAh g–1 at the rate of 200 mA g–1 after 100 cycles; G@Fe3O4@C, 920 mAh g–1 at the rate of 200 mA g–1 after 100 cycles).Keywords: 2D nanosheet; core−shell; graphene; lithium-ion battery; metal oxide
Co-reporter:Fan Jing, Miao Chen, Yanping Tang, Zhixiao Xu, Tao Huang, Yuezeng Su, Dongqing Wu
Journal of Colloid and Interface Science (15 April 2017) Volume 492() pp:
Publication Date(Web):15 April 2017
DOI:10.1016/j.jcis.2016.12.064
Nitrogen-doped mesoporous carbon nanosheets (NMCNs) with uniform hexagonal structures are fabricated via the thermal treatment of polyaniline enwrapped cobalt hydroxide (Co(OH)2) nanosheets and the subsequent acid etching of the resulting composites. It is found that the morphologies, poroisties and compositions of the NMCNs are greatly dependent on the ratio of the added aniline and Co(OH)2 nanosheets, which can in turn affect the electrochemical behavior of the NMCNs. As the electrocatalyst for oxygen reduction reaction in alkaline media, the NMCNs obtained with the aniline/Co(OH)2 ratio of ∼1.2 manifest excellent perfromance with the onset potential of −0.119 V, the half-wave potential of −0.182 V and the limiting current density of 5.06 mA cm−2, which are superior to most of the previously reported N-doped porous carbon nanosheets.Obtained by a bottom-up fabrication strategy, nitrogen-doped mesoporous carbon nanosheets with ordered hexagonal structures exhibit outstanding electrocatalytic activities towards oxygen reduction reaction.
Co-reporter:Yanping Tang, Chongqing Yang, Kan Li, Fan Jing, Ruili Liu, Dongqing Wu, Jinping Jia
Journal of Colloid and Interface Science (1 April 2017) Volume 491() pp:
Publication Date(Web):1 April 2017
DOI:10.1016/j.jcis.2016.12.037
In this work, leaf-like hybrid with Bi2O2CO3 nanotubes as the “veins” and graphene sheet as the “laminae” is fabricated via a facile one-pot reaction of bismuth nitrate and graphene oxide in alkaline aqueous solution. With the uniform distribution of Bi2O2CO3 nanotubes on the graphene substrate, the obtained Bi2O2CO3-NT/G manifests high specific surface area (90.4 m2 g−1) and large pore volume (0.197 cm3 g−1), which are favorable for the efficient light capturing together with the rapid transfer of mass and charge carriers. In comparison with the pure Bi2O2CO3 nanotubes and commercial Bi2O2CO3, Bi2O2CO3-NT/G exhibits much enhanced activity and long-term stability towards the photocatalytic degradation of organic dye pollutant, which is owing to its unique leaf-like structural features.In this work, leaf-like hybrid with Bi2O2CO3 nanotubes as the “veins” and graphene sheet as the “laminae” is fabricated via a facile one-pot reaction of bismuth nitrate and graphene oxide in alkaline aqueous solution. With the uniform distribution of Bi2O2CO3 nanotubes on the graphene substrate, the obtained Bi2O2CO3-NT/G manifests high specific surface area (90.4 m2 g−1) and large pore volume (0.197 cm3 g−1), which are favorable for the efficient light capturing and the rapid transfer of mass and charge carriers. In comparison with the pure Bi2O2CO3 nanotubes and commercial Bi2O2CO3, Bi2O2CO3-NT/G exhibits much enhanced activity and long-term stability towards the photocatalytic degradation of organic compound X-3B, which is owing to its unique leaf-like structural features.Download high-res image (112KB)Download full-size image
Co-reporter:Ruili Liu, Lixia Pan, Li Wan and Dongqing Wu
Physical Chemistry Chemical Physics 2015 - vol. 17(Issue 6) pp:NaN4729-4729
Publication Date(Web):2015/01/09
DOI:10.1039/C4CP05211K
Nitrogen-doped mesoporous carbon microfibers (NMCMFs) were prepared via an evaporation-induced tri-consistent assembly of a triblock copolymer, resols and prehydrolyzed tetraethoxy silane on natural silk followed by pyrolysis. The resultant NMCMFs inherit the advantages of both order mesoporous carbons (OMCs) and carbon microfibers (CMFs), such as uniform meso-channels, high surface area, high nitrogen content, excellent electronic conductivity as well as good flexibility. Owing to the well-designed nanostructure and the synergistic effects of the strongly coupled components, the binder-free electrodes based on NMCMFs exhibit enhanced capacity (189 F g−1 at 5 mV s−1), excellent rate capability (107 F g−1 at 100 mV s−1) and durability (maintained over 96% of the initial capacitance after 10000 cycles) in electric double-layer capacitors, outperforming those of OMCs and CMFs derived from pristine silk.
Co-reporter:Sheng Han, Jinzuan Wang, Shuang Li, Dongqing Wu and Xinliang Feng
Journal of Materials Chemistry A 2014 - vol. 2(Issue 17) pp:NaN6179-6179
Publication Date(Web):2013/11/28
DOI:10.1039/C3TA14585A
Three-dimensional (3D) macroporous graphene aerogel-supported Fe5(PO4)4(OH)3·2H2O (iron(III) hydroxide phosphate dihydrate) microspheres (GA/IHPDs) have been fabricated by the hydrothermal mineralization of Fe3+ and PO43− ions in the presence of graphene oxide (GO). The resulting hybrids own interconnected 3D macroporous frameworks with the IHPD particles (2 μm in diameter) encapsulated in flexible graphene sheets. Used as the cathode material in lithium ion batteries (LIBs), the GA/IHPDs hybrids show an excellent reversible specific capacity of 155 mA h g−1 after 300 cycles at a current density of 50 mA g−1 and maintain the specific capacities of 80 and 56 mA h g−1 at the ultrahigh current densities of 2000 and 5000 mA g−1, respectively. To our best knowledge, such an electrochemical performance of GA/IHPDs is superior to the literature reported graphene and other carbon based LiFePO4, or FePO4 hybrids. With a simple fabrication procedure and desirable electrochemical performance, this method offers a highly promising candidate for commercialized cathode materials of LIBs.
Co-reporter:Jieqiong Shan, Yuxin Liu, Ping Liu, Yanshan Huang, Yuezeng Su, Dongqing Wu and Xinliang Feng
Journal of Materials Chemistry A 2015 - vol. 3(Issue 47) pp:NaN24154-24154
Publication Date(Web):2015/10/28
DOI:10.1039/C5TA06617D
A dual-doping approach for nitrogen-doped carbon-coated SnO2–SnS/graphene nanosheets (N–C@SnO2–SnS/GN) has been developed, using hydrothermal carbonization of sucrose with SnO2-decorated graphene and ammonium thiocyanate and a subsequent thermal treatment. The resulting hybrid manifests a typical two-dimensional core–shell architecture, with a N-doped carbon coating over the SnS- and SnO2-decorated graphene nanosheets. Used as the anode material in lithium ion batteries (LIBs), N–C@SnO2–SnS/GN delivers a high specific capacity of 1236 mA h g−1 at a current density of 0.1 A g−1 after 110 cycles, which outperforms most state-of-the-art tin-based LIB anodes with core–shell structures.
Co-reporter:Yanshan Huang, Dongqing Wu, Arezoo Dianat, Manferd Bobeth, Tao Huang, Yiyong Mai, Fan Zhang, Gianaurelio Cuniberti and Xinliang Feng
Journal of Materials Chemistry A 2017 - vol. 5(Issue 4) pp:NaN1594-1594
Publication Date(Web):2016/12/01
DOI:10.1039/C6TA09161J
Hierarchically porous nitrogen-doped graphene frameworks (N-GFs) are fabricated through the ice-templating of GO with polyethylenimine and the thermal treatment of the resultant hybrids. As cathode materials in lithium ion batteries (LIBs), the obtained N-GFs exhibit an outstanding specific capacity of 379 mA h g−1 at 0.5 A g−1 for 2500 cycles. Even at an ultrahigh current density of 5 A g−1, the N-GFs maintain a capacity of 94 mA h g−1, superior to that of most reported LIB cathode materials. The experimental results and quantum mechanics calculations suggest that pyridinic-like N and pyridinic N-oxide in graphene are responsible for the excellent cathodic performance of the bipolar N-GFs by providing fast surface faradaic reactions with both p- and n-doped states.
Co-reporter:Jieqiong Shan, Yuxin Liu, Yuezeng Su, Ping Liu, Xiaodong Zhuang, Dongqing Wu, Fan Zhang and Xinliang Feng
Journal of Materials Chemistry A 2016 - vol. 4(Issue 1) pp:NaN320-320
Publication Date(Web):2015/11/17
DOI:10.1039/C5TA08109B
Graphene-directed two-dimensional (2D) nitrogen-doped porous carbon frameworks (GPF) as the hosts for sulfur were constructed via the ionothermal polymerization of 1,4-dicyanobenzene directed by the polyacrylonitrile functionalized graphene nanosheets. As cathodes for lithium–sulfur (Li–S) batteries, the prepared GPF/sulfur nanocomposites exhibited a high capacity up to 962 mA h g−1 after 120 cycles at 2 A g−1. A high reversible capacity of 591 mA h g−1 was still retained even at an extremely large current density of 20 A g−1. Such impressive electrochemical performance of GPF should benefit from the 2D hierarchical porous architecture with an extremely high specific surface area, which could facilitate the efficient entrapment of sulfur and polysulfides and afford rapid charge transfer, fast electronic conduction as well as intimate contact between active materials and the electrolyte during cycling.
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