成分配比对RuO_2-Ta_2O_5二元氧化物电容性能的影响

Effect of Composition on the Structure and Capacitive Performance of Ti/RuO_2-Ta_2O_5 Electrodes

采用热分解法制备了不同Ru/Ta配比的Ti/RuO2-Ta2O5二元混合氧化物电极材料。采用X射线衍射(XRD)、循环伏安(CV)及恒流充放电测试分析了Ti/RuO2-Ta2O5电极的组织结构、伏安特性和恒流充放电性能。结果表明,随氧化钽含量的升高,RuO2-Ta2O5涂层的结晶程度逐渐下降,当Ta2O5含量≥70mol%时,RuO2-Ta2O5混合氧化物完全以非晶态结构存在。Ti/RuO2-Ta2O5电极的比电容随Ta2O5含量的增加呈现先增后减的变化趋势。在Ta2O5含量为70mol%时,电极具有较好的超电容性能,比电容达到621.2F·g-1。

A series of binary RuO2-Ta2O5 oxide composites with different Ru/Ta molar ratios were deposited on titanium substrate by a thermal decomposition method.The structure,voltametrical characteristics and capacitive properties as a function of the Ru/Ta molar ratios were investigated by X-ray diffraction（XRD）,cyclic voltammetry（CV） and galvanostatic charge-discharge tests.The results show that the degree of crystallization of the Ti/RuO2-Ta2O5 electrodes decreases with the increase of Ta2O5 content in the RuO2-Ta2O5 oxide coatings.A completely amorphous structure exists as the proportion of Ta2O5 is up to 70 mol% or higher.The electrochemical performance of the Ti/RuO2-Ta2O5 electrodes is closely related with the composition and structure.The specific capacitance increases firstly and then decreases with the ratio of Ta to Ru in oxide coatings,and a maximum specific capacitance of 621.2 F·g-1（RuO2） is obtained when the Ta2O5 content is 70 mol%.