超级电容器RuO_2·nH_2O电极材料的热处理工艺

以RuCl_3·3H_2O水溶液为电沉积液,采用直流一示差脉冲组合电沉积技术制备超级电容器用钽基RuO_2·nH_2O薄膜阴极材料.借助扫描电镜、X射线衍射仪和电化学分析仪,研究RuO_2·nH_2O薄膜的微观形貌、物相结构、循环伏安和充放电性能.实验结果表明:RuCl_3H_2O先驱体经热处理后转变成RuO_2·nH_2O薄膜,呈不定形结构时能获得较大的比电容;随着热处理温度的升高,薄膜材料的附着力提高,RuO_2·nH_2O薄膜由不定形结构向晶体结构转变,随之薄膜的比电容下降;在300℃热处理的RuO_2·nH_2O薄膜电极材料,其比电容为466 F/g,薄膜与钽基体的附着力为11.3 MPa,薄膜的单位面积质量为2.5 mg/cm~2,1 000次充放电循环后比电容为循环前的93.1%.

Heat treatment process of RuO_2·nH_2O electrode material for supercapacitor

RuO_2·nH_2O film as a potential cathode material for supercapacitor was deposited on tantalum foils using water solution of RuCl_3·3H_2O by galvanostatic-differential pulse voltammetry. The micro-morphology, composition phases and cyclic voltammetry of the film were studied by scanning electron microscope, X-ray diffraction and electrochemical method respectively. The results show that RuCl_3·3H_2O film precursor transforms into RuO_2·nH_2O after the heat treatment, and has bigger special capacitance when RuO_2·nH_2O is amorphous structure. The adhesive force of the film is improved and there is a change for RuO_2·nH_2O from amorphous to crystal and the special capacitance of film is reduced as the heat treatment temperature increases. When the film is heat treated at 300 ℃, the adhesive force of the film is measured to be 11.3 MPa, with unit surface mass of 2.5 mg/ cm~2. The special capacitance of the film is 466 F/g, and maintains at 93.1% after 1 000 charge-discharge cycles.