(广东省稀有金属研究所，广州 510650)
摘 要: 在铱锡氯化物溶液中加入柠檬酸和乙二醇等助剂，采用刷涂-热分解法制备出钛基铱锡氧化物涂层。借助扫描电镜、电子探针、计时电流等技术研究柠檬酸与乙二醇对铱锡氧化物涂层表面形貌、结构、粗糙度和成分分布等表面性质的影响，采用循环伏安、阳极极化、交流阻抗等方法分析柠檬酸与乙二醇对铱锡氧化物涂层在硫酸溶液中电催化性能和化学稳定性的影响。结果表明：涂液中添加柠檬酸和乙二醇可细化电极表面涂层中的氧化物晶粒，明显减小涂层表面中的裂纹，显著改善锡元素的分布；在0.5 mol/L硫酸溶液中，柠檬酸乙二醇助剂改性涂层的循环伏安电荷增加1.71倍，Tafel曲线斜率减小37%，析氧反应的电荷转移阻抗降低66%，开路电位提高0.13 V。
关键字: 涂层电极；铱锡氧化物；柠檬酸；乙二醇；电催化活性；化学稳定性
（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
