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通过简单的水热法以及后续热处理,成功合成介孔NiCo_2O_4微球。利用FESEM、TEM、XPS和电化学工作站对样品的表面形貌、元素价态和电化学性能进行表征。结果表明:合成的NiCo_2O_4拥有丰富的多孔纳米针状结构,表现出较高的比表面积。由于这种三维多孔纳米结构,当NiCo_2O_4微球作为电极材料时,展现出优异的电容特性,在1A·g-1的电流密度下比电容高达1 554F·g-1,而且当电流密度增加到20A·g-1时,电容保持率为87.5%。另外,在5A·g-1的电流密度下,经过2 000次的充放电循环后,比电容仍能保持初始电容的90.4%。良好的电化学性能表明,NiCo_2O_4微球是一种理想的超级电容器电极材料。
Mesoporous NiCo 2 O 4 microspheres were successfully synthesized by simple hydrothermal method and subsequent heat treatment. The surface morphology, elemental valence and electrochemical properties of the samples were characterized by FESEM, TEM, XPS and electrochemical workstation. The results show that the synthesized NiCo_2O_4 has abundant porous nano-needle structure and exhibits a high specific surface area. Due to the three-dimensional porous nanostructures, the NiCo 2 O 4 microspheres exhibit excellent capacitance characteristics at a current density of 1 A · g -1 up to 1 554 F · g -1 when used as an electrode material, and when the current density is increased to 20A · g-1, the capacitance retention was 87.5%. In addition, the current density of 5A · g-1, after 2,000 cycles of charge and discharge, the specific capacitance can still maintain the initial capacitance of 90.4%. Good electrochemical performance indicates that NiCo_2O_4 microspheres is an ideal supercapacitor electrode material.