(1. 福州大學(xué) 材料科學(xué)與工程學(xué)院，福州 350108；
2. 廈門理工學(xué)院 材料科學(xué)與工程學(xué)院，廈門 361024)
摘 要: 采用熱分解法在270℃制備鈦基RuO2-TiO2氧化物涂層電極材料。利用循環(huán)伏安、電化學(xué)阻抗譜等方法研究Ti/RuO2-TiO2電極分別在0.5 mol/L H2SO4、0.5 mol/L Na2SO4和 1.0 mol/L NaOH電解液中的超電容行為。結(jié)果表明：在酸性溶液和堿性溶液中Ti/RuO2-TiO2電極有較低的電荷轉(zhuǎn)移電阻和優(yōu)異的贗電容特性，比電容分別達(dá)到550 F/g和578 F/g；而在Na2SO4溶液中，該電極的電荷轉(zhuǎn)移電阻較高，表現(xiàn)為典型的雙電層電容特征，比電容僅為335 F/g；經(jīng)歷2000次循環(huán)充放電測(cè)試后，該電極在中性Na2SO4溶液中的穩(wěn)定性最高，荷電能力僅下降3%；在酸性H2SO4溶液和堿性NaOH溶液中，該電極的荷電能力分別下降17%和29%。結(jié)合SEM和能譜分析可知：RuO2-TiO2在Na2SO4溶液中幾乎不發(fā)生腐蝕，表現(xiàn)出良好的循環(huán)穩(wěn)定性；RuO2-TiO2涂層在NaOH溶液中發(fā)生嚴(yán)重的面腐蝕，而在H2SO4溶液中則發(fā)生嚴(yán)重的點(diǎn)蝕，導(dǎo)致活性氧化物減少，荷電能力下降。
關(guān)鍵字: 超級(jí)電容器；氧化物陽極；電解液；反應(yīng)機(jī)理
（1. College of Materials Science and Engineering, Fuzhou University, Fuzhou 350108, China;
2. College of Materials Science and Engineering, Xiamen University of Technology, Xiamen 361024, China）
Abstract: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.
Key words: supercapacitor; oxide anode; electrolyte; reaction mechanism
