四氧化三钴超级电容器电极材料的制备与研究

Preparation and study of cobaltosic oxide supercapacitor electrode materials

电极材料是决定电化学电容器性能的一个主要方面，研究与开发高性能的电极材料是人们的研究重点之一。碳电极材料比电容较小；钌等贵重金属氧化物电极材料比电容量虽然很高，但昂贵的价格限制了其实际应用。因此价格低廉、环境友好、同样具有较高氧化还原电容的过渡金属氧化物成为目前超级电容器的研究热点之一。以硝酸钴为原料，以柠檬酸为模板水热合成了前驱体，200℃热处理后得到了四氧化三钴。循环伏安、恒流放电等电化学测试表明，200℃所得四氧化三钴电极在6mol／L氢氧化钾溶液中和-0．1～0．5V（vs．SCE）电位范围内，具有较好的循环稳定性能，单电极比电容达到442F／g。为开发高性能的超级电容器电极材料提供了参考。

Electrode material is a major effect factor on performance of electrochemical capacitor, and high performance electrode material has become the focal point of research and development at present. Specific capacitance of carbon elec- trode material is low. Although the oxides of precious metals such as ruthenium give very high specific capacitance, they have the inherent disadvantage of high price. Therefore, cheap and environment-friendly transition-metal oxides known as ex- cellent electrode materials for supercapacitors with high oxidation reduction capacitance have attracted many interests of re- searchers. Precursor was prepared via hydrothermal process with cobalt nitrate as raw material and citric acid as template. After thermal treatment at 200 ℃, cobaltosic oxide （ Co304 ） was obtained. Electrochemical properties of prepared Co3 04 e- lectrode material were tested by cyclic vohammogram and galvanostatic charge/discharge measurements. Results showed Co3 04 obtained at 200 ℃ has a good cycle stability in 6 mol/L KOH electrolyte with potential range from - 0.1 to 0.5 V （ vs. SCE）. Its specific capacitance as single electrode was up to 442 F/g. This method provides a reference for development of high performance supercapacitor electrode material.