INVESTIGATION OF SURFACE MORPHOLOGY, STRUCTURE AND ELECTROCATALYTIC PROPERTIES FOR O_2 EVOLUTION OF TITANIUM BASED IrO_2+Ta_2O_5 COATINGS

作     者：J.M Hu J.X. Wu H.M Meng YR. Zhu D.B. Sun and D.J. Yang(Beijing Corrosion and Protection Center, Open Laboratory of Corrosion, Erosion and Surface Technology,University of Science and Technology Beijing, Beijing 100083, China) 

作者机构：Univ of Science and Technology Beijing Beijing China 

出 版 物：《Acta Metallurgica Sinica(English Letters)》 (金属学报（英文版）)

年 卷 期：2000年第13卷第3期

页      面：849-856页

核心收录：

学科分类：0817[工学-化学工程与技术] 0806[工学-冶金工程] 08[工学] 0807[工学-动力工程及工程热物理] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 0802[工学-机械工程] 0703[理学-化学] 0811[工学-控制科学与工程] 

主　　题：titanium based coating anode iridium oxide tantalum oxide,solid solution crystallite orientation electrocatalytic activity 

摘      要：Titanium based IrO2 +Ta2O5 oxide anodes with different compositions and pyrolysis temperatures were prepared by termodecompoisition method. By using X-ray diffraction (XRD), the structure and texture coefficient of the coatings, TC(hkl), of IrO2 rutile crystal have been tested. It showed that, the crystallization processes of IrO2 and Ta2O5 in xIrO2 +(100-x) Ta2 O5 (x is in mol%) films affected and confined each *** the mixed system, IrO2 rutile phase existed as a solid solution with Ta, and attained the maximum solubility when x=70mol%, i.e. for the coating of 70% IrO2 +*** the coatings of low iridium content or at low preparing tem pemture, (110) and (101) pwtered orientations were dominant. However, preferred growth of IrO2 weakened with increasing either iridium content or temperature. Three typical surface morphologies were observed by using scanning electron tnicroscopy(SEM). The crystallite size of the mixed oxide coatings were finest for the the film of 70%IrO2 +30%Ta2O5,and decreased with the pyrolysis tempemture. As the results of the finest crystallite segregating on sudece and the maxitnum solid solubility of Ir and Ta component in deposits, the coatings with the composition of 70%IrO2 +Ta2O5 prepared at 450℃ presented the mdrimutn electrocatalgtic activitg for O2 evolution in 0. 5M H2SO4 *** to 550℃, Ti base suffered to oxidation resulting in decreasing anode conductivity,therefore, coatings performed a low activity.