聚苯胺包覆钴酸镍复合材料的制备及电化学性能研究

Preparation and electrochemical properties of polyaniline-coated nickel cobaltate composites

导电聚合物、过渡金属氧化物、碳材料是新型的超级电容器电极材料,超级电容器的性能与电极材料、电解液及其使用的隔膜有关,而电极材料是其中最主要的影响因素,因为它是超级电容器的重要依托,电极材料性能的好坏直接影响到电容器性能的好坏。故合理构建电极材料结构一直是储能领域的研究热点。采用典型的水热法制备了一种珊瑚状NiCO_(2)O_(4),在冰水浴条件下通过化学氧化法制备聚苯胺(PANI),并通过原味聚合法合成了PANI包覆的NiCO_(2)O_(4)(PANI@NiCO_(2)O_(4))复合材料,有效地解决了过渡金属氧化物的导电率差、比表面积低、活性物质易团聚等问题。并对PANI@NiCO_(2)O_(4)纳米复合材料结构和形貌进行表征,将其用作超级电容器的电极材料,在三电极体系下测试电化学性能。结果表明:NiCO_(2)O_(4)@PANI在1A/g的电流密度时比电容为892F/g,相比纯PANI比电容提升207.8%,相比NiCO_(2)O_(4)材料比电容提升75.9%。在10A/g电流密度下4000次充放电循环后比电容保持率为95%,具有良好的循环稳定性。因此,PANI@NiCO_(2)O_(4)是很有前途的超级电容器电极材料。

Conductive polymers,transition metal oxides and carbon materials are new supercapacitor electrode materials.The performance of supercapacitor is related to the electrode materials,electrolyte and its used diaphragm,and the electrode materials are the main influencing factor,because they are the important components supporting the supercapacitor,and the performance of electrode materials directly affects the performance of capacitor.Therefore,the reasonable construction of electrode material structure has been a hot research topic in the field of energy storage.A coral-like NiCO_(2)O_(4) was prepared by a typical hydrothermal method,and polyaniline(PANI)was prepared by chemical oxidation under ice-water bath conditions,and then PANI-coated NiCO_(2)O_(4)(PANI@NiCO_(2)O_(4))composites were synthesized by the in-situ polymerization method,which effectively solved the problems of poor electrical conductivity,low specific surface area and easy agglomeration of active substances of transition metal oxides.The structure and morphology of PANI@NiCO_(2)O_(4) nanocomposite were also characterized,and it was used as an electrode material for supercapacitors.The electrochemical properties were tested in a three-electrode system.The results showed that the specific capacitance of NiCO_(2)O_(4)@PANI was 892F/g at a current density of 1A/g,which was 207.8%higher than that of pure PANI and 75.9%higher than that of NiCO_(2)O_(4) material.The retention rate of specific capacitance was 95%after 4000 charge/discharge cycles at 10A/g current density,which had good cycling stability.The results indicated that PANI@NiCO_(2)O_(4) composites were promising electrode materials for supercapacitors.