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61.
One‐Pot Synthesis of Tunable Crystalline Ni3S4@Amorphous MoS2 Core/Shell Nanospheres for High‐Performance Supercapacitors 下载免费PDF全文
Yu Zhang Wenping Sun Xianhong Rui Bing Li Hui Teng Tan Guilue Guo Srinivasan Madhavi Yun Zong Qingyu Yan 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(30):3694-3702
Transition metal sulfides gain much attention as electrode materials for supercapacitors due to their rich redox chemistry and high electrical conductivity. Designing hierarchical nanostructures is an efficient approach to fully utilize merits of each component. In this work, amorphous MoS2 is firstly demonstrated to show specific capacitance 1.6 times as that of the crystalline counterpart. Then, crystalline core@amorphous shell (Ni3S4@MoS2) is prepared by a facile one‐pot process. The diameter of the core and the thickness of the shell can be independently tuned. Taking advantages of flexible protection of amorphous shell and high capacitance of the conductive core, Ni3S4@amorphous MoS2 nanospheres are tested as supercapacitor electrodes, which exhibit high specific capacitance of 1440.9 F g?1 at 2 A g?1 and a good capacitance retention of 90.7% after 3000 cycles at 10 A g?1. This design of crystalline core@amorphous shell architecture may open up new strategies for synthesizing promising electrode materials for supercapacitors. 相似文献
62.
Porous Hybrid Composites of Few‐Layer MoS2 Nanosheets Embedded in a Carbon Matrix with an Excellent Supercapacitor Electrode Performance 下载免费PDF全文
Hongmei Ji Chao Liu Ting Wang Jing Chen Zhengning Mao Jin Zhao Wenhua Hou Gang Yang 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(48):6480-6490
Porous hierarchical architectures of few‐layer MoS2 nanosheets dispersed in carbon matrix are prepared by a microwave‐hydrothermal method followed by annealing treatment via using glucose as C source and structure‐directing agent and (NH4)2MoS4 as both Mo and S sources. It is found that the morphology and size of the secondary building units (SBUs), the size and layer number of MoS2 nanosheets as well as the distribution of MoS2 nanosheets in carbon matrix, can be effectively controlled by simply adjusting the molar ratio of (NH4)2MoS4 to glucose, leading to the materials with a low charge–transfer resistance, many electrochemical active sites and a robust structure for an outstanding energy storage performance including a high specific capacitance (589 F g−1 at 0.5 A g−1), a good rate capability (364 F g−1 at 20 A g−1), and an excellent cycling stability (retention 104% after 2000 cycles) for application in supercapacitors. The exceptional rate capability endows the electrode with a high energy density of 72.7 Wh kg−1 and a high power density of 12.0 kW kg−1 simultaneously. This work presents a facile and scalable approach for synthesizing novel heterostructures of MoS2‐based electrode materials with an enhanced rate capability and cyclability for potential application in supercapacitor. 相似文献
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采用原位聚合的方法在活性炭表面引发噻吩聚合,制备不同配比的聚噻吩/活性炭复合材料作为超级电容器电极材料,并研究了不同配比对材料电性能及结构的影响.采用傅里叶红外光谱及场发射扫描电镜研究了材料的化学结构及表面形态.采用循环伏安,恒流充放电等方法评价了材料电性能.结果表明,当活性炭与噻吩的摩尔比为10:1时,复合材料呈蓬松... 相似文献
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Controlled Incorporation of Ni(OH)2 Nanoplates Into Flowerlike MoS2 Nanosheets for Flexible All‐Solid‐State Supercapacitors 下载免费PDF全文
Chunxue Hao Fusheng Wen Jianyong Xiang Limin Wang Hang Hou Zhibin Su Wentao Hu Zhongyuan Liu 《Advanced functional materials》2014,24(42):6700-6707
In this work, self‐supporting three‐dimensional hierarchical nanostructured MoS2@Ni(OH)2 nanocomposites are synthesized via a facile single‐mode microwave hydrothermal technique. The fabricated MoS2@Ni(OH)2 nanocomposites for supercapacitors in aqueous electrolyte exhibit higher specific capacitance and better cyclic stability than those of MoS2 and Ni(OH)2 due to the pronounced synergistic effect between MoS2 and Ni(OH)2. Further, the flexible all‐solid‐state supercapcitor is readily constructed by composing the PVA/KOH gel electrolyte in between two MoS2@Ni(OH)2 electrodes on the flexible PET substrates. The resulting supercapacitors can operate at high rate up to 1000 V/s, have excellent long‐life cycling stability, retaining 94.2% of the initial capacitance after 9000 cycles, and mechanical flexibility during extreme bending, respectively. Thereby, the MoS2@Ni(OH)2 nanocomposites are a promising electrode materials for flexible long‐life cycling all‐solid‐sate supercapacitors. 相似文献
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Alexander A. Zakhidov Dong‐Seok Suh Alexander A. Kuznetsov Joseph N. Barisci Edgar Muñoz Alan B. Dalton Steve Collins Von H. Ebron Mei Zhang John P. Ferraris Anvar A. Zakhidov Ray H. Baughman 《Advanced functional materials》2009,19(14):2266-2272
Injecting high electronic charge densities can profoundly change the optical, electrical, and magnetic properties of materials. Such charge injection in bulk materials has traditionally involved either dopant intercalation or the maintained use of a contacting electrolyte. Tunable electrochemical charge injection and charge retention, in which neither volumetric intercalation of ions nor maintained electrolyte contact is needed, are demonstrated for carbon nanotube sheets in the absence of an applied field. The tunability of electrical conductivity and electron field emission in the subsequent material is presented. Application of this material to supercapacitors may extend their charge‐storage times because they can retain charge after the removal of the electrolyte. 相似文献
70.
以微波为热源,无烟煤、炭化椰壳为原料,KOH为活化剂制备了两种超级电容器用活性炭电极材料。对比考察了两种活性炭在相同实验条件下的比电容、冲放电性能、循环稳定性、内阻;讨论了微波辐射时间对两种活性炭比电容量的影响。研究结果表明:以无烟煤、炭化椰壳为原料制备的活性炭单电极比电容分别达301F/g、266F/g,且两种活性炭均具有良好的冲放电特性;炭化椰壳制备的活性炭比无烟煤制备的活性炭循环稳定性更好,内阻更低。 相似文献