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1.
Ultrathin and Porous Ni3S2/CoNi2S4 3D‐Network Structure for Superhigh Energy Density Asymmetric Supercapacitors
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Weidong He Chenggang Wang Huiqiao Li Xiaolong Deng Xijin Xu Tianyou Zhai 《Liver Transplantation》2017,7(21)
3D‐networked, ultrathin, and porous Ni3S2/CoNi2S4 on Ni foam (NF) is successfully designed and synthesized by a simple sulfidation process from 3D Ni–Co precursors. Interestingly, the edge site‐enriched Ni3S2/CoNi2S4/NF 3D‐network is realized by the etching‐like effect of S2? ions, which made the surfaces of Ni3S2/CoNi2S4/NF with a ridge‐like feature. The intriguing structural/compositional/componental advantages endow 3D‐networked‐free‐standing Ni3S2/CoNi2S4/NF electrodes better electrochemical performance with specific capacitance of 2435 F g?1 at a current density of 2 A g?1 and an excellent rate capability of 80% at 20 A g?1. The corresponding asymmetric supercapacitor achieves a high energy density of 40.0 W h kg?1 at an superhigh power density of 17.3 kW kg?1, excellent specific capacitance (175 F g?1 at 1A g?1), and electrochemical cycling stability (92.8% retention after 6000 cycles) with Ni3S2/CoNi2S4/NF as the positive electrode and activated carbon/NF as the negative electrode. Moreover, the temperature dependences of cyclic voltammetry curve polarization and specific capacitances are carefully investigated, and become more obvious and higher, respectively, with the increase of test temperature. These can be attributed to the components' synergetic effect assuring rich redox reactions, high conductivity as well as highly porous but robust architectures. This work provides a general, low‐cost route to produce high performance electrode materials for portable supercapacitor applications on a large scale. 相似文献
2.
Direct Growth of Flower‐Like δ‐MnO2 on Three‐Dimensional Graphene for High‐Performance Rechargeable Li‐O2 Batteries
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Shuangyu Liu Yunguang Zhu Jian Xie Ying Huo Hui Ying Yang Tiejun Zhu Gaoshao Cao Xinbing Zhao Shichao Zhang 《Liver Transplantation》2014,4(9)
A challenge still remains to develop high‐performance and cost‐effective air electrode for Li‐O2 batteries with high capacity, enhanced rate capability and long cycle life (100 times or above) despite recent advances in this field. In this work, a new design of binder‐free air electrode composed of three‐dimensional (3D) graphene (G) and flower‐like δ‐MnO2 (3D‐G‐MnO2) has been proposed. In this design, graphene and δ‐MnO2 grow directly on the skeleton of Ni foam that inherits the interconnected 3D scaffold of Ni foam. Li‐O2 batteries with 3D‐G‐MnO2 electrode can yield a high discharge capacity of 3660 mAh g?1 at 0.083 mA cm?2. The battery can sustain 132 cycles at a capacity of 492 mAh g?1 (1000 mAh gcarbon ?1) with low overpotentials under a high current density of 0.333 mA cm?2. A high average energy density of 1350 Wh Kg?1 is maintained over 110 cycles at this high current density. The excellent catalytic activity of 3D‐G‐MnO2 makes it an attractive air electrode for high‐performance Li‐O2 batteries. 相似文献
3.
A three‐component, flexible electrode is developed for supercapacitors over graphitized carbon fabric, utilizing γ‐MnO2 nanoflowers anchored onto carbon nanotubes (γ‐MnO2/CNT) as spacers for graphene nanosheets (GNs). The three‐component, composite electrode doubles the specific capacitance with respect to GN‐only electrodes, giving the highest‐reported specific capacitance (308 F g?1) for symmetric supercapacitors containing MnO2 and GNs using a two‐electrode configuration, at a scan rate of 20 mV s?1. A maximum energy density of 43 W h kg?1 is obtained for our symmetric supercapacitors at a constant discharge‐current density of 2.5 A g?1 using GN–(γ‐MnO2/CNT)‐nanocomposite electrodes. The fabricated supercapacitor device exhibits an excellent cycle life by retaining ≈90% of the initial specific capacitance after 5000 cycles. 相似文献
4.
NiCo2S4 Nanosheets Grown on Nitrogen‐Doped Carbon Foams as an Advanced Electrode for Supercapacitors
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To push the energy density limit of supercapacitors, a new class of electrode materials with favorable architectures is strongly needed. Binary metal sulfides hold great promise as an electrode material for high‐performance energy storage devices because they offer higher electrochemical activity and higher capacity than mono‐metal sulfides. Here, the rational design and fabrication of NiCo2S4 nanosheets supported on nitrogen‐doped carbon foams (NCF) is presented as a novel flexible electrode for supercapacitors. A facile two‐step method is developed for growth of NiCo2S4 nanosheets on NCF with robust adhesion, involving the growth of Ni‐Co precursor and subsequent conversion into NiCo2S4 nanosheets through sulfidation process. Benefiting from the compositional features and 3D electrode architectures, the NiCo2S4/NCF electrode exhibits greatly improved electrochemical performance with ultrahigh capacitance (877 F g?1 at 20 A g?1) and excellent cycling stability. Moreover, a binder‐free asymmetric supercapacitor device is also fabricated by using NiCo2S4/NCF as the positive electrode and ordered mesoporous carbon (OMC)/NCF as the negative electrode; this demonstrates high energy density (≈45.5 Wh kg?1 at 512 W kg?1). 相似文献
5.
Zhongxue Chen Min Zhou Yuliang Cao Xinping Ai Hanxi Yang Jun Liu 《Liver Transplantation》2012,2(1):95-102
A simple ball‐milling method is used to synthesize a tin oxide‐silicon carbide/few‐layer graphene core‐shell structure in which nanometer‐sized SnO2 particles are uniformly dispersed on a supporting SiC core and encapsulated with few‐layer graphene coatings by in situ mechanical peeling. The SnO2‐SiC/G nanocomposite material delivers a high reversible capacity of 810 mA h g?1 and 83% capacity retention over 150 charge/discharge cycles between 1.5 and 0.01 V at a rate of 0.1 A g?1. A high reversible capacity of 425 mA h g?1 also can be obtained at a rate of 2 A g?1. When discharged (Li extraction) to a higher potential at 3.0 V (vs. Li/Li+), the SnO2‐SiC/G nanocomposite material delivers a reversible capacity of 1451 mA h g?1 (based on the SnO2 mass), which corresponds to 97% of the expected theoretical capacity (1494 mA h g?1, 8.4 equivalent of lithium per SnO2), and exhibits good cyclability. This result suggests that the core‐shell nanostructure can achieve a completely reversible transformation from Li4.4Sn to SnO2 during discharging (i.e., Li extraction by dealloying and a reversible conversion reaction, generating 8.4 electrons). This suggests that simple mechanical milling can be a powerful approach to improve the stability of high‐performance electrode materials involving structural conversion and transformation. 相似文献
6.
Here, a simple active materials synthesis method is presented that boosts electrode performance and utilizes a facile screen‐printing technique to prepare scalable patterned flexible supercapacitors based on manganese hexacyanoferrate‐manganese oxide and electrochemically reduced graphene oxide electrode materials (MnHCF‐MnOx/ErGO). A very simple in situ self‐reaction method is developed to introduce MnOx pseudocapacitor material into the MnHCF system by using NH4F. This MnHCF‐MnOx electrode materials can deliver excellent capacitance of 467 F g?1 at a current density of 1 A g?1, which is a 2.4 times capacitance increase compared to MnHCF. In addition a printed, patterned, flexible MnHCF‐MnOx/ErGO supercapacitor is fabricated, showing a remarkable areal capacitance of 16.8 mF cm?2 and considerable energy and power density of 0.5 mWh cm?2 and 0.0023 mW cm?2, respectively. Furthermore, the printed patterned flexible supercapacitors also exhibit exceptional flexibility, and the capacitance remains stable, even while bending to various angles (60°, 90°, and 180°) and for 100 cycles. The flexible supercapacitor arrays integrated by multiple prepared single supercapacitors can power various LEDs even in the bent states. This approach offers promising opportunities for the development of printable energy storage materials and devices with high energy density, large scalability, and excellent flexibility. 相似文献
7.
Wearable High‐Performance Supercapacitors Based on Silver‐Sputtered Textiles with FeCo2S4–NiCo2S4 Composite Nanotube‐Built Multitripod Architectures as Advanced Flexible Electrodes
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Jian Zhu Shaochun Tang Juan Wu Xiling Shi Baogang Zhu Xiangkang Meng 《Liver Transplantation》2017,7(2)
To achieve high‐performance wearable supercapacitors (SCs), a new class of flexible electrodes with favorable architectures allowing large porosity, high conductivity, and good mechanical stability is strongly needed. Here, this study reports the rational design and fabrication of a novel flexible electrode with nanotube‐built multitripod architectures of ternary metal sulfides' composites (FeCo2S4–NiCo2S4) on a silver‐sputtered textile cloth. Silver sputtering is applicable to almost all kinds of textiles, and S2? concentration is optimized during sulfidation process to achieve such architectures and also a complete sulfidation assuring high conductivity. New insights into concentration‐dependent sulfidation mechanism are proposed. The additive‐free FeCo2S4–NiCo2S4 electrode shows a high specific capacitance of 1519 F g?1 at 5 mA cm?2 and superior rate capability (85.1% capacitance retention at 40 mA cm?2). All‐solid‐state SCs employing these advanced electrodes deliver high energy density of 46 W h kg?1 at 1070 W kg?1 as well as achieve remarkable cycling stability retaining 92% of initial capacitance after 3000 cycles at 10 mA cm?2, and outstanding reliability with no capacitance degradation under large twisting. These are attributed to the components' synergy assuring rich redox reactions, high conductivity as well as highly porous but robust architectures. An almost linear increase in capacitance with devices' area indicates possibility to meet various energy output requirements. This work provides a general, low‐cost route to wearable power sources. 相似文献
8.
High‐Performance Fiber‐Shaped All‐Solid‐State Asymmetric Supercapacitors Based on Ultrathin MnO2 Nanosheet/Carbon Fiber Cathodes for Wearable Electronics
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Flexible fiber‐shaped supercapacitors have shown great potential in portable and wearable electronics. However, small specific capacitance and low operating voltage limit the practical application of fiber‐shaped supercapacitors in high energy density devices. Herein, direct growth of ultrathin MnO2 nanosheet arrays on conductive carbon fibers with robust adhesion is exhibited, which exhibit a high specific capacitance of 634.5 F g?1 at a current density of 2.5 A g?1 and possess superior cycle stability. When MnO2 nanosheet arrays on carbon fibers and graphene on carbon fibers are used as a positive electrode and a negative electrode, respectively, in an all‐solid‐state asymmetric supercapacitor (ASC), the ASC displays a high specific capacitance of 87.1 F g?1 and an exceptional energy density of 27.2 Wh kg?1. In addition, its capacitance retention reaches 95.2% over 3000 cycles, representing the excellent cyclic ability. The flexibility and mechanical stability of these ASCs are highlighted by the negligible degradation of their electrochemical performance even under severely bending states. Impressively, as‐prepared fiber‐shaped ASCs could successfully power a photodetector based on CdS nanowires without applying any external bias voltage. The excellent performance of all‐solid‐state ASCs opens up new opportunity for development of wearable and self‐powered nanodevices in near future. 相似文献
9.
General Controlled Sulfidation toward Achieving Novel Nanosheet‐Built Porous Square‐FeCo2S4‐Tube Arrays for High‐Performance Asymmetric All‐Solid‐State Pseudocapacitors
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A significant advance toward the design and fabrication of a novel hierarchical supercapacitor electrode consisting of FeCo2S4‐tubes with well‐defined square cross‐section and intersecting nanosheets built porous shells on a 3D porous Ni backbone via controlled sulfidation is reported. This general method allows template‐free synthesis of metal sulfides tubular structures with polygonal cross‐sections and also fine control over the nanostructure leading to both maximized porosity and saturation sulfidation. New insights into concentration and time dependent sulfidation reaction kinetics are proposed. The FeCo2S4 electrode achieves a specific capacitance reaching 2411 F g‐1 at 5 mA cm‐2 and good rate capability, which are superior over those for nanotube arrays of other ternary transition metal sulfides. This is attributed to rich redox reactions, the highly porous but robust architecture as well as high electrical conductivity. Especially such porous shells effectively avoid “dead volume”, thus improve the utilization ratio of the electrode material. Asymmetric solid‐state device applying the FeCo2S4 as positive electrode and N‐doped graphene hydrogel film as negative electrode has a high cell voltage of 1.6 V and thus delivers considerably higher energy density of 76.1 W h kg‐1 (at 755 W kg‐1) than those reported for similar devices. 相似文献
10.
Peng Wang Caixia Li Shihua Dong Xiaoli Ge Peng Zhang Xianguang Miao Rutao Wang Zhiwei Zhang Longwei Yin 《Liver Transplantation》2019,9(24)
The critical challenges of Li‐O2 batteries lie in sluggish oxygen redox kinetics and undesirable parasitic reactions during the oxygen reduction reaction and oxygen evolution reaction processes, inducing large overpotential and inferior cycle stability. Herein, an elaborately designed 3D hierarchical heterostructure comprising NiCo2S4@NiO core–shell arrays on conductive carbon paper is first reported as a freestanding cathode for Li‐O2 batteries. The unique hierarchical array structures can build up multidimensional channels for oxygen diffusion and electrolyte impregnation. A built‐in interfacial potential between NiCo2S4 and NiO can drastically enhance interfacial charge transfer kinetics. According to density functional theory calculations, intrinsic LiO2‐affinity characteristics of NiCo2S4 and NiO play an importantly synergistic role in promoting the formation of large peasecod‐like Li2O2, conducive to construct a low‐impedance Li2O2/cathode contact interface. As expected, Li‐O2 cells based on NiCo2S4@NiO electrode exhibit an improved overpotential of 0.88 V, a high discharge capacity of 10 050 mAh g?1 at 200 mA g?1, an excellent rate capability of 6150 mAh g?1 at 1.0 A g?1, and a long‐term cycle stability under a restricted capacity of 1000 mAh g?1 at 200 mA g?1. Notably, the reported strategy about heterostructure accouplement may pave a new avenue for the effective electrocatalyst design for Li‐O2 batteries. 相似文献
11.
A Novel Sustainable Flour Derived Hierarchical Nitrogen‐Doped Porous Carbon/Polyaniline Electrode for Advanced Asymmetric Supercapacitors
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Pingping Yu Zhiming Zhang Lingxia Zheng Feng Teng Linfeng Hu Xiaosheng Fang 《Liver Transplantation》2016,6(20)
Hierarchically porous nitrogen‐doped carbon (HPC)/polyaniline (PANI) nanowire arrays nanocomposites are synthesized by a facile in situ polymerization. 3D interconnected honeycomb‐like HPC was prepared by a cost‐effective route via one‐step carbonization using urea and alkali‐treated wheat flour as carbon precursor with a high specific surface area (1294 m2 g?1). The specific capacitances of HPC and HPC/PANI (with a surface area of 923 m2 g?1) electrode are 383 and 1080 F g?1 in 1 m H2SO4, respectively. Furthermore, an asymmetric supercapacitor based on HPC/PANI as positive electrode and HPC as negative electrode is successfully assembled with a voltage window of 0–1.8 V in 1 m Na2SO4 aqueous electrolyte, exhibiting high specific capacitance (134 F g?1), high energy density (60.3 Wh kg?1) and power density (18 kW kg?1), and excellent cycling stability (91.6% capacitance retention after 5000 cycles). 相似文献
12.
A High‐Energy Density Asymmetric Supercapacitor Based on Fe2O3 Nanoneedle Arrays and NiCo2O4/Ni(OH)2 Hybrid Nanosheet Arrays Grown on SiC Nanowire Networks as Free‐Standing Advanced Electrodes
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Jian Zhao Zhenjiang Li Xiangcheng Yuan Zhen Yang Meng Zhang Alan Meng Qingdang Li 《Liver Transplantation》2018,8(12)
In this paper, a novel freestanding core‐branch negative and positive electrode material through integrating trim aligned Fe2O3 nanoneedle arrays (Fe2O3 NNAs) is first proposed with typical mesoporous structures and NiCo2O4/Ni(OH)2 hybrid nanosheet arrays (NiCo2O4/Ni(OH)2 HNAs) on SiC nanowire (SiC NW) skeletons with outstanding resistance to oxidation and corrosion, good conductivity, and large‐specific surface area. The original built SiC NWs@Fe2O3 NNAs is validated to be a highly capacitive negative electrode (721 F g?1 at 2 A g?1, i.e., 1 F cm?2 at 2.8 mA cm?2), matching well with the similarly constructed SiC NWs@NiCo2O4/Ni(OH)2 HNAs positive electrode (2580 F g?1 at 4 A g?1, i.e., 3.12 F cm?2 at 4.8 mA cm?2). Contributed by the uniquely engineered electrodes, a high‐performance asymmetric supercapacitor (ASC) is developed, which can exhibit a maximum energy density of 103 W h kg?1 at a power density of 3.5 kW kg?1, even when charging the device within 6.5 s, the energy density can still maintain as high as 45 W h kg?1 at 26.1 kW kg?1, and the ASC manifests long cycling lifespan with 86.6% capacitance retention even after 5000 cycles. This pioneering work not only offers an attractive strategy for rational construction of high‐performance SiC NW‐based nanostructured electrodes materials, but also provides a fresh route for manufacturing next‐generation high‐energy storage and conversion systems. 相似文献
13.
Hao Chen Linfeng Hu Yan Yan Renchao Che Min Chen Limin Wu 《Liver Transplantation》2013,3(12):1636-1646
A facile one‐step hydrothermal co‐deposition method for growth of ultrathin Ni(OH)2‐MnO2 hybrid nanosheet arrays on three dimensional (3D) macroporous nickel foam is presented. Due to the highly hydrophilic and ultrathin nature of hybrid nanosheets, as well as the synergetic effects of Ni(OH)2 and MnO2, the as‐fabricated Ni(OH)2‐MnO2 hybrid electrode exhibits an ultrahigh specific capacitance of 2628 F g?1. Moreover, the asymmetric supercapacitor with the as‐obtained Ni(OH)2‐MnO2 hybrid film as the positive electrode and the reduced graphene oxide as the negative electrode has a high energy density (186 Wh kg?1 at 778 W kg?1), based on the total mass of active materials. 相似文献
14.
Phase Transformation Induced Capacitance Activation for 3D Graphene‐CoO Nanorod Pseudocapacitor
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Yun Guang Zhu Ye Wang Yumeng Shi Zhi Xiang Huang Lin Fu Hui Ying Yang 《Liver Transplantation》2014,4(9)
Development of a pseudocapacitor over the integration of metal oxide on carbonaceous materials is a promising step towards energy storage devices with high energy and power densities. Here, a self‐assembled cobalt oxide (CoO) nanorod cluster on three‐dimensional graphene (CoO‐3DG) is synthesized through a facile hydrothermal method followed by heat treatment. As an additive‐free electrode, CoO‐3DG exhibits good electrochemical performance. Compared with CoO nanorod clusters grown on Ni foam (i.e., CoO‐Ni, ≈680 F g?1 at 1 A g?1 and ≈400 F g?1 at 20 A g?1), CoO‐3DG achieves much higher capacitance (i.e., ≈980 F g?1 at 1 A g?1 and ≈600 F g?1 at 20 A g?1) with excellent cycling stability of 103% retention of specific capacitance after 10 000 cycles. Furthermore, it shows an interesting activation process and instability with a redox reaction for CoO. In addition, the phase transformation from CoO nanorods to Co3O4 nanostructures was observed and investigated after charge and discharge process, which suggests the activation kinetics and the phase transformable nature of CoO based nanostructure. These observations demonstrate phase transformation with morphological change induced capacitance increasement in the emergent class of metal oxide materials for electrochemical energy storage device. 相似文献
15.
Exploring Advanced Sandwiched Arrays by Vertical Graphene and N‐Doped Carbon for Enhanced Sodium Storage
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Dong Xie Xinhui Xia Yu Zhong Yadong Wang Donghuang Wang Xiuli Wang Jiangping Tu 《Liver Transplantation》2017,7(3)
Smart hybridization of active materials into tailored electrode structure is highly important for developing advanced electrochemical energy storage devices. With the help of sandwiched design, herein a powerful strategy is developed to fabricate three‐layer sandwiched composite core/shell arrays via combined hydrothermal and polymerization approaches. In such a unique architecture, wrinkled MoSe2 nanosheets are sandwiched by vertical graphene (VG) core and N‐doped carbon (N‐C) shell forming sandwiched core/shell arrays. Interesting advantages including high electrical conductivity, strong mechanical stability, and large porosity are combined in the self‐supported VG/MoSe2/N‐C sandwiched arrays. As a preliminary test, the sodium ion storage properties of VG/MoSe2/N‐C sandwiched arrays are characterized and demonstrated with high capacity (540 mA h g?1), enhanced high rate capability, and long‐term cycling stability (298 mA h g?1 at 2.0 A g?1 after 1000 cycles). The sandwiched core/shell structure plays positive roles in the enhancement of electrochemical performances due to dual conductive carbon networks, good volume accommodation, and highly porous structure with fast ion diffusion. The directional electrode design protocol provides a general method for synthesis of high‐performance ternary core/shell electrodes. 相似文献
16.
Changsheng An Yifei Yuan Bao Zhang Linbo Tang Bin Xiao Zhenjiang He Junchao Zheng Jun Lu 《Liver Transplantation》2019,9(18)
Pseudocapacitance is a Faradaic process that involves surface or near surface redox reactions. Increasing the pseudocapacitive contribution is one of the most effective means to improve the rate performance of electrode materials. In this study, graphene oxide is used as a template to in situ synthesize burr globule‐like FeSe2/graphene hybrid (B‐FeSe2/G) using a facile one‐step hydrothermal method. Structural characterization demonstrates that graphene layers not only wrap the surfaces of FeSe2 particles, but also stretch into the interior of these particles, as a result of which the unique nano‐microsphere structure is successfully established. When serving as anode material for Na‐ion batteries, B‐FeSe2/G hybrid displays high electrochemical performance in the voltage range of 0.5–2.9 V. The B‐FeSe2/G hybrid has high reversible capacity of 521.6 mAh·g?1 at 1.0 A g?1. Meanwhile, after 400 cycles, high discharge capacity of 496.3 mAh g?1 is obtained at a rate of 2.5 A g?1, with a high columbic efficiency of 96.6% and less than 1.0% loss of discharge capacity. Even at the ultrahigh rate of 10 A g?1, a specific capacity of 316.8 mAh g?1 can be achieved. Kinetic analyses reveal that the excellent performance of the B‐FeSe2/G hybrid is largely attributed to the high pseudocapacitive contribution induced by the special nano‐micro structure. 相似文献
17.
Leyla Najafi Sebastiano Bellani Reinier Oropesa‐Nuñez Alberto Ansaldo Mirko Prato Antonio Esau Del Rio Castillo Francesco Bonaccorso 《Liver Transplantation》2018,8(16)
2D transition metal‐dichalcogenides are emerging as efficient and cost‐effective electrocatalysts for the hydrogen evolution reaction (HER). However, only the edge sites of their trigonal prismatic phase show HER‐electrocatalytic properties, while the basal plane, which is absent of defective/unsaturated sites, is inactive. Herein, the authors tackle the key challenge of increasing the number of electrocatalytic sites by designing and engineering heterostructures composed of single‐/few‐layer MoSe2 flakes and carbon nanomaterials (graphene or single‐wall carbon nanotubes) produced by solution processing. The electrochemical coupling between the materials that comprise the heterostructure effectively enhances the HER‐electrocatalytic activity of the native MoSe2 flakes. The optimization of the mass loading of MoSe2 flakes and their electrode assembly via monolithic heterostructure stacking provides a cathodic current density of 10 mA cm?2 at overpotential of 100 mV, a Tafel slope of 63 mV dec?1, and an exchange current density (j0) of 0.203 µA cm?2. In addition, thermal and chemical treatments are exploited to texturize the basal planes of the MoSe2 flakes (through Se‐vacancies creation) and to achieve in situ semiconducting‐to‐metallic phase conversion, respectively, thus they activate new HER‐electrocatalytic sites. The as‐engineered electrodes show a 4.8‐fold enhancement of j0 and a decrease in the Tafel slope to 54 mV dec?1. 相似文献
18.
Xiao Wang Yaguang Li Sen Wang Feng Zhou Pratteek Das Chenglin Sun Shuanghao Zheng Zhong‐Shuai Wu 《Liver Transplantation》2020,10(22)
Rechargeable aqueous zinc‐ion batteries (ZIBs) are appealing due to their high safety, zinc abundance, and low cost. However, developing suitable cathode materials remains a great challenge. Herein, a novel 2D heterostructure of ultrathin amorphous vanadium pentoxide uniformly grown on graphene (A‐V2O5/G) with a very short ion diffusion pathway, abundant active sites, high electrical conductivity, and exceptional structural stability, is demonstrated for highly reversible aqueous ZIBs (A‐V2O5/G‐ZIBs), coupling with unprecedented high capacity, rate capability, long‐term cyclability, and excellent safety. As a result, 2D A‐V2O5/G heterostructures for stacked ZIBs at 0.1 A g?1 display an ultrahigh capacity of 489 mAh g?1, outperforming all reported ZIBs, with an admirable rate capability of 123 mAh g?1 even at 70 A g?1. Furthermore, the new‐concept prototype planar miniaturized zinc‐ion microbatteries (A‐V2O5/G‐ZIMBs), demonstrate a high volumetric capacity of 20 mAh cm?3 at 1 mA cm?2, long cyclability; holding high capacity retention of 80% after 3500 cycles, and in‐series integration, demonstrative of great potential for highly‐safe microsized power sources. Therefore, the exploration of such 2D heterostructure materials with strong synergy is a reliable strategy for developing safe and high‐performance energy storage devices. 相似文献
19.
Hollow NiCo2S4 Nanospheres Hybridized with 3D Hierarchical Porous rGO/Fe2O3 Composites toward High‐Performance Energy Storage Device
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Yan Wang Zexiang Chen Tao Lei Yuanfei Ai Zhenkai Peng Xinyu Yan Hai Li Jijun Zhang Zhiming M. Wang Yu‐Lun Chueh 《Liver Transplantation》2018,8(16)
Hierarchical hollow NiCo2S4 microspheres with a tunable interior architecture are synthesized by a facile and cost‐effective hydrothermal method, and used as a cathode material. A three‐dimensional (3D) porous reduced graphene oxide/Fe2O3 composite (rGO/Fe2O3) with precisely controlled particle size and morphology is successfully prepared through a scalable facile approach, with well‐dispersed Fe2O3 nanoparticles decorating the surface of rGO sheets. The fixed Fe2O3 nanoparticles in graphene efficiently prevent the intermediates during the redox reaction from dissolving into the electrolyte, resulting in long cycle life. KOH activation of the rGO/Fe2O3 composite is conducted for the preparation of an activated carbon material–based hybrid to transform into a 3D porous carbon material–based hybrid. An energy storage device consisting of hollow NiCo2S4 microspheres as the positive electrode, the 3D porous rGO/Fe2O3 composite as the negative electrode, and KOH solution as the electrolyte with a maximum energy density of 61.7 W h kg?1 is achieved owing to its wide operating voltage range of 0–1.75 V and the designed 3D structure. Moreover, the device exhibits a high power density of 22 kW kg?1 and a long cycle life with 90% retention after 1000 cycles at the current density of 1 A g?1. 相似文献
20.
Ice Templated Free‐Standing Hierarchically WS2/CNT‐rGO Aerogel for High‐Performance Rechargeable Lithium and Sodium Ion Batteries
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Ye Wang Dezhi Kong Wenhui Shi Bo Liu Glenn Joey Sim Qi Ge Hui Ying Yang 《Liver Transplantation》2016,6(21)
A hybrid nanoarchitecture aerogel composed of WS2 nanosheets and carbon nanotube‐reduced graphene oxide (CNT‐rGO) with ordered microchannel three‐dimensional (3D) scaffold structure was synthesized by a simple solvothermal method followed by freeze‐drying and post annealing process. The 3D ordered microchannel structures not only provide good electronic transportation routes, but also provide excellent ionic conductive channels, leading to an enhanced electrochemical performance as anode materials both for lithium‐ion batteries (LIBs) and sodium‐ion batteries (SIBs). Significantly, WS2/CNT‐rGO aerogel nanostructure can deliver a specific capacity of 749 mA h g?1 at 100 mA g?1 and a high first‐cycle coulombic efficiency of 53.4% as the anode material of LIBs. In addition, it also can deliver a capacity of 311.4 mA h g?1 at 100 mA g?1, and retain a capacity of 252.9 mA h g?1 at 200 mA g?1 after 100 cycles as the anode electrode of SIBs. The excellent electrochemical performance is attributed to the synergistic effect between the WS2 nanosheets and CNT‐rGO scaffold network and rational design of 3D ordered structure. These results demonstrate the potential applications of ordered CNT‐rGO aerogel platform to support transition‐metal‐dichalcogenides (i.e., WS2) for energy storage devices and open up a route for material design for future generation energy storage devices. 相似文献