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951.
《Advanced Materials Interfaces》2018,5(12)
Flexible energy storage devices are leading to many researches owing to the huge development prospects, especially the energy storage materials. Recently, ZnS/NiCo2S4/Co9S8 nanotube (ZNCN) is synthesized by adding rod‐like ZnO during hydrothermal process, differing from previous reports. The capacitance of ZNCN electrode is 1618.1 F g−1 at the current density of 1 A g−1 in 2 m KOH, a 1.2‐fold enhancement with respect to the pristine NiCo2S4/Co9S8 (NC) (1348 F g−1), a 1.44‐fold enhancement with respect to the pristine NiCo2S4 (1127 F g−1). ZNCN electrode maintains 77% of the original specific capacitance after 5000 cycles at 15 A g−1. An asymmetric supercapacitor is assembled using ZNCN as its positive electrode and the hydrated ferric oxide (FeOOH) deposited on the carbon cloth as negative electrode (ZNCN//FeOOH) to demonstrate performance. The as‐assembled device can operate in a voltage region of 1.6 V, at a power density of 0.75 kW kg−1, the energy density reaches 66 Wh kg−1, when solid‐state electrolyte and diaphragm are assembled into a flexible solid‐state device, it can successfully light up the LED light. The ZNCN in this study may provide a new material for flexible electronic devices, while providing a new strategy for energy storage applications. 相似文献
952.
《Advanced Materials Interfaces》2018,5(14)
Metal–organic frameworks materials have shown great potential in energy storage and conversion research, but their poor electrical conductivity and inferior chemical stability limit their applications. Herein, an in situ‐grown crosslinked nickel–cobalt hydroxides@carbon nanotubes composite with a nanosheet‐covered hollow structure is rationally designed and synthesized successfully from ZIF‐67@carbon nanotubes. Different from other studies, the carbon nanotubes in this composite penetrate the hollow structure, and the active nanosheets also grow on the parts protruding from the hollow boxes via this in situ synthetic route. Compare with pure nickel–cobalt hydroxides, the composite exhibits enhanced electroactivity in terms of the specific capacity and cycling performance. In particular, it delivers a high specific capacity of 916.8 C g−1 at 1 A g−1 and ≈79.0% of its initial value preserves after 4000 cycles. This facile synthetic approach enables the preparation of crosslinked metal–organic framework materials with the potential to meet the demands of energy storage and conversion devices as well as supercapacitors. 相似文献
953.
《Advanced Materials Technologies》2018,3(1)
Over the last decade, significant efforts have been made to develop electrode architectures of the electrochemical energy storage (EES) devices. The involvement of electrostatic field, magnetic field, and electromagnetic field for electrode fabrication plays a vital role to enhance performance of supercapacitors in comparison with conventional roots. Electromagnetic techniques are advantageous over others because of several reasons including material's interactions at molecular level, noncontact energy, and chemical transportations to extract physical phase changings, and large‐scale production with a cost‐effective way. Recently, these techniques became a powerful tool for constructing hierarchical and well‐ordered nanostructured electrodes. Their novel mechanisms and forms show high efficiency with numerous advantages such as green, simple, and mild reaction conditions. Herein, recent progress involving electromagnetic techniques for supercapacitor is reviewed; their potential future applications are also highlighted. The present review aims to serve as a guideline for fabrication techniques of next generation supercapacitor electrodes. 相似文献
954.
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956.
G. Udhaya Sankar C. Ganesa Moorthy G. RajKumar 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2018,40(10):1209-1214
Two graphite rods from two empty mosquito repellent refills were employed for synthesis of few-layered graphene for material developments on batteries and supercapacitor applications. The graphene sheet is isolated from graphite rod via electrochemical exfoliation method. We exfoliate graphene by intercalating sodium dodecyl benzene sulfonate at a constant concentration with constant DC power supply. The purified graphene is characterized by scanning electron microscopy, Fourier transform infrared spectrometry, Raman spectrometry, X-ray diffraction, and X-ray photoelectron spectroscopy. A newly promised approach in the production of energy source material by utilizing empty repellent rods has been explored. 相似文献
957.
Abdelhakim Elmouwahidi Esther Bailón‐García Agustín F. Pérez‐Cadenas Nerea Fernández‐Sáez Francisco Carrasco‐Marín 《Advanced functional materials》2018,28(35)
Vanadium‐coated carbon‐xerogel microspheres are successfully prepared by a specific designed sol–gel method, and their supercapacitor behavior is tested in a two‐electrode system. Nitrogen adsorption shows that these composite materials present a well‐developed micro‐ and mesoporous texture, which depends on the vanadium content in the final composite. A high dispersion of vanadium oxide on the carbon microsphere surface is reached, being the vanadium particle size around 4.5 nm. Moreover, low vanadium oxidation states are stabilized by the carbon matrix in the composites. The complete electrochemical characterization of the composites is carried out using cyclic voltammetry, chronopotentiometry, cycling charge–discharge, and impedance spectroscopy. The results show that these composites present high capacitance as 224 F g?1, with a high capacitance retention which is explained on the basis of the presence of vanadium oxide, texture, and chemistry surface. 相似文献
958.
《Advanced functional materials》2018,28(35)
Highly flexible supercapacitors (SCs) have great potential in modern electronics such as wearable and portable devices. However, ultralow specific capacity and low operating potential window limit their practical applications. Herein, a new strategy for the fabrication of free‐standing Ni? Mo? S and Ni? Fe? S nanosheets (NSs) for high‐performance flexible asymmetric SC (ASC) through hydrothermal and subsequent sulfurization technique is reported. The effect of Ni2+ is optimized to attain hierarchical Ni? Mo? S and Ni? Fe? S NS architectures with high electrical conductivity, large surface area, and exclusive porous networks. Electrochemical properties of Ni? Mo? S and Ni? Fe? S NS electrodes exhibit that both have ultrahigh specific capacities (≈312 and 246 mAh g?1 at 1 mA cm?2), exceptional rate capabilities (78.85% and 78.46% capacity retention even at 50 mA cm?2, respectively), and superior cycling stabilities. Most importantly, a flexible Ni? Mo? S NS//Ni? Fe? S NS ASC delivers a high volumetric capacity of ≈1.9 mAh cm?3, excellent energy density of ≈82.13 Wh kg?1 at 0.561 kW kg?1, exceptional power density (≈13.103 kW kg?1 at 61.51 Wh kg?1) and an outstanding cycling stability, retaining ≈95.86% of initial capacity after 10 000 cycles. This study emphasizes the potential importance of compositional tunability of the NS architecture as a novel strategy for enhancing the charge storage properties of active electrodes. 相似文献
959.
《Advanced functional materials》2018,28(37)
Heteroatom‐doped carbon nanomaterials with high surface area and tunable microporosity are important but they generally require difficult and multistep syntheses. Herein, a simple and straightforward strategy is introduced that involves a wrap‐bake‐sublime approach to synthesize microporosity controlled and heteroatom codoped carbon nanocages. A zinc‐containing zeolitic imidazolate framework (ZIF‐8) core is wrapped in a cross‐linked oligomer containing nitrogen and phosphorus, oligo(cyclotriphosphazene‐co‐hexahydroxytriphenylene) (OCHT). As‐synthesized core–shell ZIF‐8‐OCHT nanoparticles are baked at high temperatures to sublimate zinc through OCHT shell, resulting in a porous structure. Meanwhile, hollow cavities are introduced into N,P codoped carbon nanocages (NPCNs) via the sacrificial nature of ZIF‐8 template. The microporosity is finely tuned by controlling thickness of the OCHT shell during synthesis of the core–shell nanoparticles, since the sublimation tendency of zinc component at high temperatures depends on the thickness of OCHT shell. A systematic correlation between the electrochemical performance of NPCNs and their microporosity is confirmed. Furthermore, the electrochemical performance of the NPCNs is related to the degree of heteroatom codoping. The approach is successfully scaled‐up without compromising their electrochemical performance. Finally, a symmetric and flexible all‐solid‐state‐supercapacitor with high energy and power density, and a long‐term cycleability is demonstrated (75% capacitance retention after 20 000 cycles). 相似文献
960.