(廣東省稀有金屬研究所，廣州 510650)
摘 要: 在銥錫氯化物溶液中加入檸檬酸和乙二醇等助劑，采用刷涂-熱分解法制備出鈦基銥錫氧化物涂層。借助掃描電鏡、電子探針、計(jì)時(shí)電流等技術(shù)研究檸檬酸與乙二醇對銥錫氧化物涂層表面形貌、結(jié)構(gòu)、粗糙度和成分分布等表面性質(zhì)的影響，采用循環(huán)伏安、陽極極化、交流阻抗等方法分析檸檬酸與乙二醇對銥錫氧化物涂層在硫酸溶液中電催化性能和化學(xué)穩(wěn)定性的影響。結(jié)果表明：涂液中添加檸檬酸和乙二醇可細(xì)化電極表面涂層中的氧化物晶粒，明顯減小涂層表面中的裂紋，顯著改善錫元素的分布；在0.5 mol/L硫酸溶液中，檸檬酸乙二醇助劑改性涂層的循環(huán)伏安電荷增加1.71倍，Tafel曲線斜率減小37%，析氧反應(yīng)的電荷轉(zhuǎn)移阻抗降低66%，開路電位提高0.13 V。
關(guān)鍵字: 涂層電極；銥錫氧化物；檸檬酸；乙二醇；電催化活性；化學(xué)穩(wěn)定性
（Guangdong Research Institute of Rare Metals, Guangzhou 510650, China）
Abstract:The Ir-Sn oxide coatings on titanium were prepared using brush painting-thermal decomposition of inorganic salt solution containing iridium chloride and stannic chloride modified by citric acid and ethylene glycol. The effects of citric acid and ethylene glycol on the surface morphology, structure, roughness and elements distribution of IrO2-SnO2 coatings were studied with scanning electron microscope, X-ray diffractometer, chronoamperometer and electron microprobe, respectively. The influences of citric acid and ethylene glycol on the electrocatalytic activity and chemical stability of IrO2-SnO2 coatings were also investigated by cyclic voltammetry, anodic polarization and AC impedance. The results show that, citric acid and ethylene glycol may reduce the size of oxides grains in coating, cracks on the coating, and improve the Sn element distribution. The cyclic voltammetric charge of the modified coating in 0.5 mol/L sulfuric acid solution increases by 1.71 times; the slope of Tafel curve decreases by 37%; the charge transfer impedance of oxygen evolution reaction decreases by 66%. In addition, the open circuit potential increases by 0.13 V.
Key words: coated electrode; Ir-Sn oxide; citric acid; ethylene glycol; eletrocatalytic activity; chemical stability
