三维结构钴镍基双金属硫化物对超级电容器的影响[*]

采用水热法成功制备出三维结构NiCo2O4和NiCo2S4纳米材料,将其应用于超级电容器电极材料。通过XRD对材料的物相组成进行分析,用SEM和TEM对材料的表面形貌和结构进行观察分析,三维结构有利于电解液对电极材料浸润,从而极大地提升材料电化学性能。通过恒电流充放电、交流阻抗和长循环等电化学实验测试对比分析发现,双金属硫化物相比于氧化物具有更加优异的电化学性能,主要是由于硫元素具有更小的电负性且电化学反应活性较高。NiCo2S4电极材料恒电流充放电及长循环测试容量保持率分别为79.69%和76.66% ,与NiCo2O4材料的68.1%和59.64%相比展现出优异的稳定性能。

Effect of three dimensional Cobalt-nickel based bimetallic sulfide on supercapacitors

Indium in NiCo2O4 and NiCo2S4 nanomaterials with 3D structure were prepared by hydrothermal method and applied to electrode materials of supercapacitor. The phase composition of the material was analyzed by XRD, and the surface morphology and structure of the material were observed and analyzed by SEM and TEM. The three-dimensional structure was conducive to the electrolyte infiltration of the electrode material, thus greatly improving the electrochemical performance of the material. The comparative analysis of electrochemical experiments such as constant current charge-discharge, AC impedance and long cycle shows that bimetallic sulfide has better electrochemical performance than oxide, mainly because sulfur element has lower electronegativity and higher electrochemical reactivity. The constant current charge-discharge and long-cycle capacity retention rates of NiCo2S4 electrode material are 79.69% and 76.66%, respectively, showing excellent stability compared with 68.1% and 59.64% of NiCo2O4 electrode material.