电解液对Ti/RuO_2-TiO_2电极电容性能的影响  

Effect of electrolyte on capacitive performance of Ti/RuO_2-TiO_2 electrodes

作　　者：陈志杰[1] 朱君秋[2] 邵艳群[1] 伊昭宇 唐电[1] 

机构地区：[1]福州大学材料科学与工程学院,福州350108 [2]厦门理工学院材料科学与工程学院,厦门361024

出　　处：《中国有色金属学报》2016年第12期2580-2588,共9页The Chinese Journal of Nonferrous Metals

基　　金：国家自然科学基金资助项目(11374053);福建省自然科学基金资助项目(2015J01190)~~

摘　　要：采用热分解法在270℃制备钛基RuO_2-TiO_2氧化物涂层电极材料。利用循环伏安、电化学阻抗谱等方法研究Ti/RuO_2-TiO_2电极分别在0.5 mol/L H_2SO_4、0.5 mol/L Na_2SO_4和1.0 mol/L NaOH电解液中的超电容行为。结果表明:在酸性溶液和碱性溶液中Ti/RuO_2-TiO_2电极有较低的电荷转移电阻和优异的赝电容特性,比电容分别达到550 F/g和578 F/g;而在Na_2SO_4溶液中,该电极的电荷转移电阻较高,表现为典型的双电层电容特征,比电容仅为335 F/g;经历2000次循环充放电测试后,该电极在中性Na_2SO_4溶液中的稳定性最高,荷电能力仅下降3%;在酸性H_2SO_4溶液和碱性NaOH溶液中,该电极的荷电能力分别下降17%和29%。结合SEM和能谱分析可知:RuO_2-TiO_2在Na_2SO_4溶液中几乎不发生腐蚀,表现出良好的循环稳定性;RuO_2-TiO_2涂层在NaOH溶液中发生严重的面腐蚀,而在H_2SO_4溶液中则发生严重的点蚀,导致活性氧化物减少,荷电能力下降。RuO2-TiO2 coating were prepared by thermal decomposition method on pure titanium TA2 substrate at 270 ℃. The supercapacitor behavior of RuO2-TiO2 coating was investigated by cyclic voltammetry（CV）, electrochemical impedance spectroscopy （EIS） and charging-discharging test in 0.5 mol/L H2SO4, 0.5 mol/L Na2SO4 and 1.0 mol/L NaOH electrolytes, respectively. The results show that the Ti/RuO2-TiO2 electrode has low charge transfer resistance in acidic and alkaline electrolytes, and the specific capacitance of 550 F/g and 578 F/g are obtained in these two electrolytes, respectively. Conversely, the electrode has relative higher charge transfer resistance and lower specific capacitance （335 F/g） in neutral Na2SO4 electrolyte than that of in acidic and alkaline electrolytes. However, the electrode losing 17% and 29% of the maximum capacity after 2000 charging-discharging cycles in acidic and alkaline electrolytes, respectively, but just only 3% lost in neutral Na2SO4 solution. Combined with the SEM and EDS analysis, the electrode is hardly corroded in Na2SO4 solution, thus exhibits good cycle stability. In contrast, Ti/RuO2-TiO2 electrodes occur serious surface corrosion in NaOH solution, while occurring serious pitting corrosion in H2SO4 solution. Severe corrosion results in a significantly reduction of active substance, and thus reduces the charge capacity of the electrode.

关 键 词：超级电容器 氧化物阳极 电解液 反应机理 

分 类 号：TM531[电气工程—电器]