Co-reporter:Ling Fan, Qian Liu, Zhi Xu, and Bingan Lu
ACS Energy Letters July 14, 2017 Volume 2(Issue 7) pp:1614-1614
Publication Date(Web):June 8, 2017
DOI:10.1021/acsenergylett.7b00378
Potassium-based dual-ion full batteries (PDIBs) were developed with graphite anode, polytriphenylamine (PTPAn) cathode, and KPF6-based electrolyte. The PDIBs delivered a reversible capacity of 60 mA h g–1 at a median discharge voltage of 3.23 V at 50 mA g–1, with superior rate performance and long-term cycling stability over 500 cycles (capacity retention of 75.5%). Unlike the traditional dual-ion batteries, the operation mechanism of the PDIBs with PTPAn cathode is that the PF6– ions interacted with the nitrogen atom reversibly in the PTPAn cathode and the K+ ions were intercalated/deintercalated into/from the graphite anode during the charge/discharge process.
Co-reporter:Ling Fan;Qian Liu;Suhua Chen;Zhi Xu
Advanced Energy Materials 2017 Volume 7(Issue 14) pp:
Publication Date(Web):2017/07/01
DOI:10.1002/aenm.201602778
Sodium-based dual ion full batteries (NDIBs) are reported with soft carbon as anode and graphite as cathode for the first time. The NDIBs operate at high discharge voltage plateau of 3.58 V, with superior discharge capacity of 103 mA h g−1, excellent rate performance, and long-term cycling stability over 800 cycles with capacity retention of 81.8%. The mechanism of Na+ and PF6− insertion/desertion during the charging/discharging processes is proposed and discussed in detail, with the support of various spectroscopies.
Co-reporter:Suhua Chen, Ling Fan, Lingling Xu, Qian Liu, Yong Qin, Bingan Lu
Energy Storage Materials 2017 Volume 8(Volume 8) pp:
Publication Date(Web):1 July 2017
DOI:10.1016/j.ensm.2017.03.011
Lithium ion batteries (LIBs) are still suffering from the issues of low capacity, limited lifespan and poor rate performance. To address these issues, FeS-hollow core-shell structure with ultrathin carbon coated composite (H-FeS@C) were synthesized and used for high rate LIBs. The ultra-thin carbon matrix wrapped on the surface of FeS can enhance the electric conductivity and protect the electrode, while the hollow structure can adjust large volume expansion during cycling. Benefiting from its unique structure, the H-FeS@C core-shell composite delivers high capacity, remarkable cycling stability (with reversible capacity of 100 mA h g-1 after 100 K cycles at 80,000 mA g-1) and high rate performance. Moreover, when charging at 200 mA g-1 and discharging at 10,000 mA g-1, the battery delivers a reversible capacity of 540 mA h g-1 after 100 cycles with capacity retention of 86%. The superior electrochemical properties of H-FeS@C may provide a new method for designing new materials with high rate and long-term stability.
Co-reporter:Yuhua Yang, Jun Zhou, Zhi Xu, Ling Fan, Bingan Lu
Materials Letters 2017 Volume 207(Volume 207) pp:
Publication Date(Web):15 November 2017
DOI:10.1016/j.matlet.2017.07.034
•Biological application of using bacteria in electrochemical energy storage.•In situ fabricate freestanding flexible Ni12P5 –carbon @ RGO paper anode.•The Ni12P5 particles are perfectly and fully coated by bacteria based carbon.•The nature yolk-shell-structure can afford volume expansion of charge/discharge.A freestanding flexible Ni12P5 – carbon @ reduced graphene oxides (RGO) paper was in-situ fabricated by using bacteria to absorb and encapsulate the metal Ni2+ completely. It presented excellent performances such as long cycle-life, high capacity, excellent coulombic efficiency and superior rate performance during charge/discharge processes. Specially, its high conductivity and robust mechanical flexibility may be used in wearable devices or other fields.
Co-reporter:Qifa Cheng, Jing Xu, Tao Wang, Ling Fan, Ruifang Ma, Xinzhi Yu, Jian Zhu, Zhi Xu, Bingan Lu
Applied Surface Science 2017 Volume 422(Volume 422) pp:
Publication Date(Web):15 November 2017
DOI:10.1016/j.apsusc.2017.05.225
•We synthesised the TiO2 and Au dual quantum dots (QDs) on three-dimensional graphene flowers (Au@TiO2@3DGFs) for PEC hydrogen production.•The 3DGFs as a scaffold for dual QDs can provide more active sites and more stable structure.•The newly-developed Au@TiO2@3DGFs composite exhibited a surprisingly PEC activity and excellent durability.Photoelectrocatalysis (PEC) has been demonstrated as a promising technique for hydrogen production. However, the high over-potential and high recombination rate of photo-induced electron-hole pairs lead to poor hydrogen production efficiency. In order to overcome these problems, TiO2 and Au dual quantum dots (QDs) on three-dimensional graphene flowers (Au@TiO2@3DGFs) was synthesized by an electro-deposition strategy. The combination of Au and TiO2 modulates the band gap of TiO2, shifts the absorption to visible lights and improves the utilization efficiency of solar light. Simultaneously, the size-quantization TiO2 on 3DGFs not only achieves a larger specific surface area over conventional nanomaterials, but also promotes the separation of the photo-induced electron-hole pairs. Besides, the 3DGFs as a scaffold for QDs can provide more active sites and stable structure. Thus, the newly-developed Au@TiO2@3DGFs composite exhibited an impressive PEC activity and excellent durability. Under −240 mV potential (vs. RHE), the photoelectric current density involved visible light illumination (100 mW cm−2) reached 90 mA cm−2, which was about 3.6 times of the natural current density (without light, only 25 mA cm−2). It worth noting that the photoelectric current density did not degrade and even increased to 95 mA cm−2 over 90 h irradiation, indicating an amazing chemical stability.
Co-reporter:Erjin Zhang, Bin Wang, Xinzhi Yu, Jingyi Zhu, Longlu Wang, Bingan Lu
Energy Storage Materials 2017 Volume 8(Volume 8) pp:
Publication Date(Web):1 July 2017
DOI:10.1016/j.ensm.2017.05.012
Sodium ion batteries (SIBs) have attracted extensive attention in recent years. However, the large volume change of cathode materials during the charge and discharge processes impedes the progress and application of SIBs. In this paper, three-dimensional (3D) tetsubo-like Beta-iron oxy-hydroxide (β-FeOOH) nano-cuboids on carbon nanotubes (CNTs) are synthesized by a simple solution method and used as cathode for SIBs. The β-FeOOH exhibits a (2×2) tunnel-type configuration, which can provide huge space for reversible sodium. The radial distribution of β-FeOOH nano-cuboids on the CNTs provides plenty cushion space and sufficient contact area with electrolyte during charge and discharge processes. Furthermore, the CNTs can enhance the electric conductivity and prevent the nanocomposite from agglomeration. Benefiting from the unique structure, the hybridization nanocomposite delivers a high initial discharge capacity (271 mA h g−1 at 10 mA g−1), long cycle life (120 mA h g−1 after 150 cycles with ~0.1% capacity decay per cycle at 120 mA g−1) and high rate performance (118 mA h g−1 at a current density of 240 mA g−1). These results indicate that the β-FeOOH@CNTs nanocomposite electrode may be a promising candidate for SIBs. Our work may provide a new way to construct and design high-performance cathode electrode materials for SIBs and related systems.
Co-reporter:Xiaoyan Wang;Ling Fan;Decai Gong;Jian Zhu;Qingfeng Zhang
Advanced Functional Materials 2016 Volume 26( Issue 7) pp:1104-1111
Publication Date(Web):
DOI:10.1002/adfm.201504589
Germanium is considered as a promising anode material because of its comparable lithium and sodium storage capability, but it usually exhibits poor cycling stability due to the large volume variation during lithium or sodium uptake and release processes. In this paper, germanium@graphene nanofibers are first obtained through electrospinning followed by calcination. Then atomic layer deposition is used to fabricate germanium@graphene@TiO2 core–shell nanofibers (Ge@G@TiO2 NFs) as anode materials for lithium and sodium ion batteries (LIBs and SIBs). Graphene and TiO2 can double protect the germanium nanofibers in charge and discharge processes. The Ge@G@TiO2 NFs composite as an anode material is versatile and exhibits enhanced electrochemical performance for LIBs and SIBs. The capacity of the Ge@G@TiO2 NFs composite can be maintained at 1050 mA h g−1 (100th cycle) and 182 mA h g−1 (250th cycle) for LIBs and SIBs, respectively, at a current density of 100 mA g−1, showing high capacity and good cycling stability (much better than that of Ge nanofibers or Ge@G nanofibers).
Co-reporter:Jing Xu, Shaozhen Gu, Ling Fan, Patrick Xu, Bingan Lu
Electrochimica Acta 2016 Volume 196() pp:125-130
Publication Date(Web):1 April 2016
DOI:10.1016/j.electacta.2016.01.228
Lotus root-like CoMoO4@graphene nanofibers(CoMoO4@G NFs) was prepared by electrospinning along with post heat treatment, and used as high-performance anode for lithium ion batteries (LIBs). Compared with the pure CoMoO4 NFs, the prepared lotus root-like CoMoO4@G NFs electrode displays higher reversible capacity of 735 mA h g−1 at 100 mA g−1, better rate capability and cycling stability (capacity retains 80% based on the second cycle even after 200 cycles,). These results highlight the importance of combination of conductive graphene nanosheets with multi-level porous CoMoO4 NFs for high-performance LIBs.
Co-reporter:Yuhua Yang, Jian Zhu, Wei Shi, Jun Zhou, Decai Gong, Shaozhen Gu, Lei Wang, Zhi Xu, Binan Lu
Materials Letters 2016 Volume 177() pp:34-38
Publication Date(Web):15 August 2016
DOI:10.1016/j.matlet.2016.04.168
•The 3D nanoporous ZnWO4 material is fabricated by electrospinning method.•It can resist a high charge and discharge current with a little capacitance fading.•Little penetrable porous space and 3D branches connect each other in a large area.•Increasing active sites assure the electronic transmission.A new three-dimensional (3D) nanoporous ZnWO4 nanoparticles with WCl6 and Zn(NO3)2·6H2O as the precursors was prepared by electrospinning through a simple and facile progress of electrospinning. The 3D nanoporous ZnWO4 nanoparticles(3DN ZnWO4) were used as the electrode for supercapacitor application, and the electrochemical performance was analyzed, indicating the 3DN ZnWO4 supercapacitor is an ideal electrode material with an outstanding cycle, high specific capacitance and excellent rate capacitance, especially it can resist a high current charge and discharge with a little capacitance fading(specific capacitance decreases only 10% with the current density being increased from 40 A g−1 to 100 A g−1).
Co-reporter:Mei Wu, Ling Fan, Ruifang Ma, Jian Zhu, Shaozhen Gu, Tao Wang, Decai Gong, Zhi Xu, Bingan Lu
Materials Letters 2016 Volume 182() pp:15-18
Publication Date(Web):1 November 2016
DOI:10.1016/j.matlet.2016.06.060
•NiO and CrO3 surface decorate Ni nanofibers were prepared via electrospinning.•It shows highly effective and stable electrocatalytic for HER.•It's current density achieves 100 mA cm−2 at 228 mV versus RHE.•It shows superior advantages such as low cost, easy preparation and energy-saving.Electrocatalysts are of great importance for water splitting to produce hydrogen. Here, NiO and CrO3 double surface-decorate Ni (Ni@NiO@CrO3) nanofibers were prepared by electrospinning as highly effective and stable electrocatalysts for hydrogen evolution reaction. It shows high electrocatalytic activity (100 mA cm−2 at a low overpotential versus RHE at 228 mV) and superior stability (after 120 h without decay). The excellent electrocatalytic activity of Ni@NiO@CrO3 nanofibers is account for the well distribution of CrO3 nanoparticles and the good conductivity of Ni nanowires. As CrO3 nanoparticles are partly embedded in the nanofibers, they are difficult to peel off from the Ni@NiO nanofibers, enabling a good stability of the hybrid materials.
Co-reporter:Jian Zhu, Tao Wang, Fengru Fan, Lin Mei, and Bingan Lu
ACS Nano 2016 Volume 10(Issue 9) pp:8243
Publication Date(Web):July 27, 2016
DOI:10.1021/acsnano.6b04522
Development of electrode materials with high capability and long cycle life are central issues for lithium-ion batteries (LIBs). Here, we report an architecture of three-dimensional (3D) flexible silicon and graphene/carbon nanofibers (FSiGCNFs) with atomic-scale control of the expansion space as the binder-free anode for flexible LIBs. The FSiGCNFs with Si nanoparticles surrounded by accurate and controllable void spaces ensure excellent mechanical strength and afford sufficient space to overcome the damage caused by the volume expansion of Si nanoparticles during charge and discharge processes. This 3D porous structure possessing built-in void space between the Si and graphene/carbon matrix not only limits most solid-electrolyte interphase formation to the outer surface, instead of on the surface of individual NPs, and increases its stability but also achieves highly efficient channels for the fast transport of both electrons and lithium ions during cycling, thus offering outstanding electrochemical performance (2002 mAh g–1 at a current density of 700 mA g–1 over 1050 cycles corresponding to 3840 mAh g–1 for silicon alone and 582 mAh g–1 at the highest current density of 28 000 mA g–1).Keywords: atomic scale; flexible lithium-ion batteries; graphene/carbon nanofibers; silicon; ultrastable anodes
Co-reporter:Yuhua Yang, Bin Wang, Jingyi Zhu, Jun Zhou, Zhi Xu, Ling Fan, Jian Zhu, Ramakrishna Podila, Apparao M. Rao, and Bingan Lu
ACS Nano 2016 Volume 10(Issue 5) pp:5516
Publication Date(Web):May 3, 2016
DOI:10.1021/acsnano.6b02036
The development of freestanding flexible electrodes with high capacity and long cycle-life is a central issue for lithium-ion batteries (LIBs). Here, we use bacteria absorption of metallic Mn2+ ions to in situ synthesize natural micro-yolk–shell-structure Mn2P2O7–carbon, followed by the use of vacuum filtration to obtain Mn2P2O7–carbon@reduced graphene oxides (RGO) papers for LIBs anodes. The Mn2P2O7 particles are completely encapsulated within the carbon film, which was obtained by carbonizing the bacterial wall. The resulting carbon microstructure reduces the electrode–electrolyte contact area, yielding high Coulombic efficiency. In addition, the yolk–shell structure with its internal void spaces is ideal for sustaining volume expansion of Mn2P2O7 during charge/discharge processes, and the carbon shells act as an ideal barrier, limiting most solid–electrolyte interphase formation on the surface of the carbon films (instead of forming on individual particles). Notably, the RGO films have high conductivity and robust mechanical flexibility. As a result of our combined strategies delineated in this article, our binder-free flexible anodes exhibit high capacities, long cycle-life, and excellent rate performance.Keywords: bacteria; binder-free flexible anode; lithium-ion batteries; reduced graphene oxides; yolk−shell Mn2P2O7−carbon
Co-reporter:Ling Fan, Ruifang Ma, Yuhua Yang, Suhua Chen, Bingan Lu
Nano Energy 2016 Volume 28() pp:304-310
Publication Date(Web):October 2016
DOI:10.1016/j.nanoen.2016.08.056
•The covalent sulfur was used for room temperature sodium-sulfur batteries.•The covalent sulfur could prevent the formation and the dissolution of sodium polysulfide.•Covalent sulfur based carbonaceous materials exhibit excellent electrochemical performance.The room temperature sodium-sulfur (RT Na-S) batteries have attracted extensive attention due to its low cost and high specific energy. Yet, RT Na-S batteries usually suffer from low reversible capacity, short lifespan and inferior Coulombic efficiency. Herein, covalent sulfur based carbonaceous materials was investigated for RT Na-S battery to address these drawbacks. Generally, the covalent S could prevent the formation of sodium polysulfide (Na2Sn, 4≤n≤8) effectively, further avoid the dissolution of sodium polysulfide into electrolyte; besides, the covalent S in these carbonaceous materials is reversible during charge/discharge process, which is good for cycling stability. Benefiting from these merits, the covalent sulfur based materials delivers high reversible capacity over 1000 mA h g−1, long cycling stability for 900 cycles with capacity decay of 0.053% per cycle and superior Coulombic efficiency approximately 100%. This study may provide a new method for designing high performance RT Na-S batteries.Covalent sulfur based carbonaceous electrode was investigated as electrodes for room temperature sodium-sulfur batteries. It delivers high reversible capacity, long cycling stability for 900 cycles and superior Coulombic efficiency approximately 100%. This study may provide a new method for designing high performance RT Na-S batteries.
Co-reporter:Lin Mei;Haitao Zhao
Advanced Science 2015 Volume 2( Issue 12) pp:
Publication Date(Web):
DOI:10.1002/advs.201500116
Recently, a growing amount of effort has been devoted to solving the widespread problem of pollution. Photocatalysts have attracted increasing attention for their widespread environmental applications. Here, a classic and simple electrospun technique is used to directly fabricate a porous a tungsten oxide nanoframework with graphene film as a photocatalyst for degradation of pollutants. The as-synthesized film simultaneously possesses substantial adsorptivity of aromatic molecules, extensive light absorption range, significant light trapping, and efficient charge carrier separation properties, which remarkably enhance photocatalytic activity. In the photodegradation of Rhodamine B, a significant photocatalytic enhancement in the reaction rate is observed, which has superior photocatalytic activity compared to other bare WO3 and TiO2 nanomaterials under visible-light irradiation.
Co-reporter:Jing Xu, Shaozhen Gu and Bingan Lu
RSC Advances 2015 vol. 5(Issue 88) pp:72046-72050
Publication Date(Web):20 Aug 2015
DOI:10.1039/C5RA10571D
We demonstrate humidity sensing with SnO2@G–GO nanocomposites using three important parameters for a sensing device: sensitivity, response and recovery time, and stability. Here, the SnO2@G–GO nanocomposites were fabricated by classical electrospinning and solution evaporation. The as-prepared SnO2@G–GO sensor demonstrated very high sensitivity (up to 32 MΩ/% RH), fast response and recovery time (less than 1 s), and good stability. Pure SnO2 and SnO2@G hybrid NFs were prepared as reference materials for humidity sensing. And they showed low sensitivity and slow response to humid air. The performance for the incorporation of graphene and graphene oxide with SnO2 to greatly improve the humidity sensing properties were discussed in detail.
Co-reporter:Jian Zhu, Libao Chen, Zhi Xu, Bingan Lu
Nano Energy 2015 Volume 12() pp:339-346
Publication Date(Web):March 2015
DOI:10.1016/j.nanoen.2014.10.026
•We have introduced a novel super high-throughput needless electrospinning method to prepare flexible FUIn2O3@AUCNFF which was used as electrodes in LIBs.•The novel strategy can be further extended to prepare various metal oxides@aligned ultralong carbon nanofiber film.•The flexible FUIn2O3@AUCNFF exhibited excellent cycling performance, anodic capacity, and rate capacity.Flexible lithium-ion batteries (LIBs) are of increasing interest as mobile power supply for the next-generation of flexible electronics. The current flexible LIBs are generally limited by relatively poor ductility, short cycle-life and low charge and discharge rate. Herein, we report a rational design and preparation of flexible ultra-long, aligned carbon nanofibers thin films with embedded In2O3 nanocrystals (In2O3@FUACNFF) as a binder free anode for highly flexible LIBs. In this work, needleless electrospinning has been demonstrated to be to an effective method for the preparation of In2O3@FUACNFF with super-high throughput. The In2O3@FUACNFF can ensure excellent charge transport, electrolyte transport and mechanical flexibility, thus leading to excellent electrochemical performance and exceptional flexibility. The In2O3@FUACNFF exhibited excellent cycling ability even after 500 cycles, with a capacity of 545.6 mA h g−1 at a current density of 200 mA g−1 and rate performance even at the highest current density of 100 A g−1 with a reversible capacity of 224.2 mA h g−1. Moreover, highly flexible full batteries were also fabricated to demonstrate the superior durability (the electrical stability of the manufactured flexible full battery was hardly affected after more than 120 times folding cycles), excellent cycle-ability (the capacity retention was almost 100% in the measured range from the 17th cycle on) and high rate performance (321.4 mA h g−1 at a current density of 1000 mA g−1).
Co-reporter:Xinzhi Yu;Zhi Xu
Advanced Materials 2014 Volume 26( Issue 7) pp:1044-1051
Publication Date(Web):
DOI:10.1002/adma.201304148
Co-reporter:Ting Yang and Bingan Lu
Physical Chemistry Chemical Physics 2014 vol. 16(Issue 9) pp:4115-4121
Publication Date(Web):02 Dec 2013
DOI:10.1039/C3CP54144D
SnO2 is a promising high-capacity anode material for lithium-ion batteries (LIBs), but it usually exhibits poor cycling stability due to its huge volume variation during the lithium uptake and release process. In this work, SnO2 nanofibers and nanotubes with highly porous (HPNFs, HPNTs) structure have been synthesized by a facile emulsion electrospinning and subsequent calcination process in air at 500 °C. Pores with a diameter range of 2–30 nm were distributed evenly on the surface of the nanofibers and nanotubes. The HPNFs and HPNTs manifested high capacities and excellent cycle performance as the anode electrode for LIBs, and they can deliver reversible capacities of 583 and 645 mA h g−1 at a current density of 100 mA g−1 after 50 cycles, respectively. When the current density is up to 5 A g−1, the electrodes still exhibit a good retention, and the reversible capacities were about 370 and 432 mA h g−1, which performs much better than the nanofibers and nanotubes without a porous structure. Our results demonstrated that this simple method could be extended for the synthesis of porous metal oxide nanotubes with high performances in the applications of lithium ion batteries and other fields.
Co-reporter:Jian Zhu, Guanhua Zhang, Shaozhen Gu, Bingan Lu
Electrochimica Acta 2014 150() pp: 308-313
Publication Date(Web):
DOI:10.1016/j.electacta.2014.10.149
Co-reporter:Jian Zhu, Zhi Xu, Bingan Lu
Nano Energy 2014 Volume 7() pp:114-123
Publication Date(Web):July 2014
DOI:10.1016/j.nanoen.2014.04.010
•We have developed a novel strategy to fabricate NiCo2O4@Au nanotubes which were used as electrodes both in supercapacitors and Li-Ion Batteries.•The novel strategy can be further extended to prepare various bi-metal oxides@metal nanoparticles.•NiCo2O4@Au NTs were also used as the positive electrode to fabricate an asymmetric supercapacitor device with high energy density and high power density.•We presented new mechanisms of Au NPs as mechanical anchoring centers to adjacent NiCo2O4 nanoparticles to explain this superior cycling stability for both SCs and LIBs.Novel NiCo2O4@Au nanotubes (NTs) with a mesporous structure and hollow interiors have been synthesized by the electrospinning method followed by calcination in air. For supercapacitor application, the specific capacitance of NiCo2O4@Au NTs reached 1013.5 F g−1 and could be maintained at 85.13% after 10,000 cycles at a current density of 10 A g−1. The NiCo2O4@Au NTs were also used as the positive electrode to fabricate an asymmetric supercapacitor device with a maximum voltage of 1.45 V. The device exhibited high energy density (~19.56 Wh kg−1), high power density (~2115.01 W kg−1 at 2.75 Wh kg−1) and outstanding cycling stability (79.05% retention after 4000 times). For LIBs application, the as-obtained NiCo2O4@Au nanotube electrodes showed a high reversible capacity of 732.5 mA h g−1 even after 200th cycles at a current density of 100 mA g−1 with good cycling stability. Au nanoparticles had not only penetrated into the whole electrode to form three dimensional percolation networks but also served as adhesion centers or mechanic anchoring points to tightly hold the adjacent NiCo2O4 particles together, which led to the superior tolerance ability of this electrode to volume expansion due to strain or stress from faster ion/electron transfer during cycling.
Co-reporter:Yuejiao Chen, Jian Zhu, Baihua Qu, Bingan Lu, Zhi Xu
Nano Energy 2014 Volume 3() pp:88-94
Publication Date(Web):January 2014
DOI:10.1016/j.nanoen.2013.10.008
•Propose a concept for the construction of NiCo2O4/graphene hybrid nanosheet arrays.•The incorporation of graphene into NiCo2O4 array exhibits improved Li-storage properties.•High capacity of 806 mA h g−1 was retained without obvious decay.•Graphene was bonded into the NiCo2O4 sheets to improve the intrinsic conductivity of NiCo2O4 and effectively buffer the strain induced by lithiation.NiCo2O4 is a potential lithium-ion battery (LIB) anode material that can be applied to the industrial production for commercial applications. However, the capacity and cycling stability of the LIB based on NiCo2O4 should be improved first. Herein, graphene-based NiCo2O4 nanosheet arrays directly grown on nickel foam have been successfully synthesized. This composites array shows significantly improved lithium storage properties with higher reversible capacity and better cycling stability than NiCo2O4 nanosheets. The three-dimensional graphene not only serves as a conductive network to increase the conductivity of the NiCo2O4, but also can offer effective buffering to accommodate the lithiation-induced stress which is beneficial to lithium storage and cycling stability.Graphene-based NiCo2O4 nanosheet arrays directly grown on nickel foam have been successfully synthesized. The incorporation of graphene into the composites array shows significantly improved lithium storage properties than NiCo2O4 nanosheets. The graphene not only serves as a conductive network to increase the conductivity of the NiCo2O4, but also can offer effective buffering to accommodate the lithiation-induced stress which is beneficial to lithium storage and cycling stability.
Co-reporter:Jian Zhu, Guanhua Zhang, Xinzhi Yu, Qiuhong Li, Bingan Lu, Zhi Xu
Nano Energy 2014 Volume 3() pp:80-87
Publication Date(Web):January 2014
DOI:10.1016/j.nanoen.2013.10.009
•We have developed a novel double protection strategy to fabricate SnO2@G@G composite.•The novel double protection strategy can be further extended to prepare various metal oxides (MOs)@G@G.•SnO2@G@G nanostructure greatly enhanced cycling performance, anodic capacity, and rate capacity.SnO2 is considered as one of the most promising anode material because of its high lithium storage capability. However, poor cycling performance caused by serious aggregation and considerable volume change upon cycling hampers its industrial application. In this paper, a simple synthesis route is demonstrated for the preparation of SnO2@graphene@graphene (SnO2@G@G) for Lithium ion battery applications. The graphene was initially treated using strong sonicate to form numerous highly dispersed small graphene nanosheets (SGNSs) in the solution. SnO2@graphene (SnO2@G) composite is obtained in the form of a nonwoven mat by electrospinning followed by calcination at 450 °C in air. SnO2@G@G composite was prepared by using a simple solution mixing method. The novel SnO2@G@G composite exhibits enhanced electrochemical performance as anode material for LIBs. Furthermore, this simple and efficient synthesis strategy is versatile and can be extended to fabrication of various types of composites between graphene and metal oxides which could be widely used in many fields, like transparent and flexibility electrode.
Co-reporter:Guanhua Zhang, Huigao Duan, Bingan Lu and Zhi Xu
Nanoscale 2013 vol. 5(Issue 13) pp:5801-5808
Publication Date(Web):23 Apr 2013
DOI:10.1039/C3NR01085F
The hybrid structure of nanoparticle-decorated nanotubes has the advantage of both large specific surface areas of nanoparticles and anisotropic properties of nanotubes, which is desirable for many applications. In this study, Ag nanoparticles on highly porous TiO2 nanotubes (NTs) on both internal and external sidewalls (Ag@TiO2@Ag NTs) are directly synthesized by emulsion electrospinning and thermal evaporation for the first time. The Ag@TiO2@Ag NT heterostructures, which have large surface-to-volume ratios, improved electrical conductivity, and an excellent material synergetic effect, demonstrate excellent electrochemical properties and superior photocatalytic performance. The new method for the synthesis of Ag@TiO2@Ag NT heterostructures can be applied to fabricate various types of other novel metal nanoparticles (for example Au and Pt) on highly porous nanotubes on both internal and external sidewalls. The possible growth mechanism and reasons for excellent electrochemical properties and superior photocatalytic performance were discussed in detail.
Co-reporter:Bingan Lu, Xiaodong Li, Taihong Wang, Erqing Xie and Zhi Xu
Journal of Materials Chemistry A 2013 vol. 1(Issue 12) pp:3900-3906
Publication Date(Web):21 Jan 2013
DOI:10.1039/C3TA01444D
The hybrid structure of nanoparticle-decorated nanotubes has the advantage of both large specific surface areas of nanoparticles and anisotropic properties of nanotubes, which is desirable for many applications. In this study, WO3 nanoparticles decorated on highly porous TiO2 nanotubes along both internal and external sidewalls (WO3@TiO2@WO3 heterostructures) were synthesized through emulsion electrospinning, thermal evaporation, and thermal annealing. The WO3@TiO2@WO3 heterostructures had large specific surface areas, high porous structure and excellent interface (between WO3 nanoparticles and TiO2 nanotubes). Three other samples, TiO2 nanofibers, TiO2 nanotubes, and TiO2 nanofibers decorated by WO3 nanoparticles, were prepared in order to compare with the WO3@TiO2@WO3 heterostructures for photocatalysis with both UV and visible light irradiation. The new material (WO3@TiO2@WO3 heterostructures) had a wide range of light absorption and demonstrated the best photocatalytic performance. The possible growth mechanism and reasons for high photocatalysis are discussed in detail.
Co-reporter:Haitao Zhao, Bingan Lu, Jing Xu, Erqing Xie, Taihong Wang and Zhi Xu
Nanoscale 2013 vol. 5(Issue 7) pp:2835-2839
Publication Date(Web):05 Feb 2013
DOI:10.1039/C3NR34300F
The hybrid structure of nanoparticle-decorated highly porous nanotubes combines the advantages of large specific surface areas of nanoparticles and anisotropic properties of highly porous nanotubes, which is desirable for many applications, including batteries, photoelectrochemical water splitting, and catalysis. Here, we report a novel emulsion electrospinning–thermal treatment method to synthesize the nanoparticles deposited on both side walls of nanotubes with two unique characteristics: (1) large loading amount of nanoparticles per highly porous nanotubes (with the morphology of nanoparticles); (2) intimate contact between nanoparticles and highly porous nanotubes. Both features are advantageous for the above applications that involve both surface reactions and charge transportation processes. Moreover, the emulsion electrospinning–thermal treatment method is simple and straightforward, with which we have successfully decorated various highly porous metal oxide nanotubes with metal oxide or noble metal nanoparticles. The new method will have an impact on diverse technologies such as lithium ion batteries, catalysts, and photoelectrochemical devices.
Co-reporter:Jian Zhu, Danni Lei, Guanhua Zhang, Qiuhong Li, Bingan Lu and Taihong Wang
Nanoscale 2013 vol. 5(Issue 12) pp:5499-5505
Publication Date(Web):09 Apr 2013
DOI:10.1039/C3NR00467H
SnOx is a promising high-capacity anode material for lithium-ion batteries (LIBs), but it usually exhibits poor cycling stability because of its huge volume variation during the lithium uptake and release process. In this paper, SnOx carbon nanofibers (SnOx@CNFs) are firstly obtained in the form of a nonwoven mat by electrospinning followed by calcination in a 0.02 Mpa environment at 500 °C. Then we use a simple mixing method for the synthesis of SnOx@CNF@graphene (SnOx@C@G) nanocomposite. By this technique, the SnOx@CNFs can be homogeneously deposited in graphene nanosheets (GNSs). The highly scattered SnOx@C@G composite exhibits enhanced electrochemical performance as anode material for LIBs. The double protection strategy to improve the electrode performance through producing SnOx@C@G composites is versatile. In addition, the double protection strategy can be extended to the fabrication of various types of composites between metal oxides and graphene nanomaterials, possessing promising applications in catalysis, sensing, supercapacitors and fuel cells.
Co-reporter:Guanhua Zhang, Taihong Wang, Xinzhi Yu, Haonan Zhang, Huigao Duan, Bingan Lu
Nano Energy 2013 Volume 2(Issue 5) pp:586-594
Publication Date(Web):September 2013
DOI:10.1016/j.nanoen.2013.07.008
•Synthesis of hierarchical Co3O4@NiCo2O4 nanoforest with a facile fabrication strategy.•Hierarchical nanoforest structures greatly enhanced the performance of supercapacitors.•Large specific surface areas and extra electronic transmission channels can enhanced the performance of supercapacitors.Nanoforest of hierarchical Co3O4@NiCo2O4 nanowire arrays were synthesized via a facile strategy for electrochemical supercapacitors. The smart combination of Co3O4 and NiCo2O4 nanostructures in the nanowire arrays shows a promising synergistic effect for capacitors with greatly enhanced performance. A high areal capacitance of 2.04 F cm−2 at the scan rate of 5 mV s−1 and 0.79 F cm−2 (almost 2.5 times as high as that of pristine Co3O4) even at 30 mA cm−2 after 6000 cycles with varying current densities were achieved. Particularly, when the current turned back to 10 mA cm−2 after the above cycles with large current, 1.18 F cm−2, corresponding to 83.7% of the initial capacitance, can be recovered and maintains for another 1500 cycles without noticeable decrease. These results show that the nanoforest of hierarchical Co3O4@NiCo2O4 nanowire arrays could be a promising electrode material for high-performance electrochemical capacitors.
Co-reporter:Qingfeng Zhang, Zhi Xu, Bingan Lu
Energy Storage Materials (July 2016) Volume 4() pp:84-91
Publication Date(Web):1 July 2016
DOI:10.1016/j.ensm.2016.03.005
Li-ion batteries (LIBs) with ultrafast charge and slow/fast discharge capability are highly desirable. Meanwhile, sustainable hydrogen produced by water splitting with high efficiency and low cost is another technique of great interest to industry. In this paper, we proposed to apply strongly coupled MoS2–3D graphene hybrid (MoS2@GF) with freestanding receptaculum nelumbinis-like (RNL) structure both as a binderfree electrode for LIBs and as a catalyst for high efficient water splitting application. The hybrid (RNL MoS2@GF) based electrodes of LIBs showed ultrafast charging and slow discharging capability (The 60s-charging LIB could discharge as long as 3000 s) and excellent cycle stability (the specific capacity had almost no change after 100 cycles). More importantly, the binderfree RNL MoS2@GF as water-splitting catalyst exhibited high activity and superior stability for hydrogen-evolution reaction in acidic solutions, which lasted more than 200 h without any decay, with a current of 160 mA cm−2 at an overpotential of 350 mV.Download high-res image (519KB)Download full-size image
Co-reporter:Bingan Lu, Xiaodong Li, Taihong Wang, Erqing Xie and Zhi Xu
Journal of Materials Chemistry A 2013 - vol. 1(Issue 12) pp:NaN3906-3906
Publication Date(Web):2013/01/21
DOI:10.1039/C3TA01444D
The hybrid structure of nanoparticle-decorated nanotubes has the advantage of both large specific surface areas of nanoparticles and anisotropic properties of nanotubes, which is desirable for many applications. In this study, WO3 nanoparticles decorated on highly porous TiO2 nanotubes along both internal and external sidewalls (WO3@TiO2@WO3 heterostructures) were synthesized through emulsion electrospinning, thermal evaporation, and thermal annealing. The WO3@TiO2@WO3 heterostructures had large specific surface areas, high porous structure and excellent interface (between WO3 nanoparticles and TiO2 nanotubes). Three other samples, TiO2 nanofibers, TiO2 nanotubes, and TiO2 nanofibers decorated by WO3 nanoparticles, were prepared in order to compare with the WO3@TiO2@WO3 heterostructures for photocatalysis with both UV and visible light irradiation. The new material (WO3@TiO2@WO3 heterostructures) had a wide range of light absorption and demonstrated the best photocatalytic performance. The possible growth mechanism and reasons for high photocatalysis are discussed in detail.
Co-reporter:Ting Yang and Bingan Lu
Physical Chemistry Chemical Physics 2014 - vol. 16(Issue 9) pp:NaN4121-4121
Publication Date(Web):2013/12/02
DOI:10.1039/C3CP54144D
SnO2 is a promising high-capacity anode material for lithium-ion batteries (LIBs), but it usually exhibits poor cycling stability due to its huge volume variation during the lithium uptake and release process. In this work, SnO2 nanofibers and nanotubes with highly porous (HPNFs, HPNTs) structure have been synthesized by a facile emulsion electrospinning and subsequent calcination process in air at 500 °C. Pores with a diameter range of 2–30 nm were distributed evenly on the surface of the nanofibers and nanotubes. The HPNFs and HPNTs manifested high capacities and excellent cycle performance as the anode electrode for LIBs, and they can deliver reversible capacities of 583 and 645 mA h g−1 at a current density of 100 mA g−1 after 50 cycles, respectively. When the current density is up to 5 A g−1, the electrodes still exhibit a good retention, and the reversible capacities were about 370 and 432 mA h g−1, which performs much better than the nanofibers and nanotubes without a porous structure. Our results demonstrated that this simple method could be extended for the synthesis of porous metal oxide nanotubes with high performances in the applications of lithium ion batteries and other fields.
