水解沉积--阳极氧化法形成Al-Ti复合氧化膜

通过含钛无机盐的水解沉积及高温热处理,铝电极箔表面形成高介电常数氧化物———TiO2 膜层,然后在己二酸铵溶液中恒电流阳极氧化,形成 Al Ti复合氧化膜。AFM观测了含钛无机盐水解沉积过程中,铝电极箔表面形貌的变化。在铬酸和磷酸的混合溶液中测试了氧化膜的耐电压随溶解时间的变化。通过SIMS检测了复合氧化膜中 Al3 、Ti4 的强度随溅射时间的变化。膜溶解试验及 SIMS 检测结果表明Al Ti复合氧化膜由 3 层组成,外层和中间层为 Al、Ti、O不同配比的混合物,内层则为纯的 Al2O3。铝电极箔比容随氧化膜耐电压的变化关系曲线表明,60V耐电压下,Al Ti复合氧化膜的比容提高率为51%。

Formation of Al-Ti composite oxide films on aluminum by hydrolysis precipitation and anodizing

Aluminum specimens were covered with TiO_2 film by hydrolysis precipitation of inorganic salt and subsequently heating, and then anodized galvanostatically in ammonium adipate solution,by which Al-Ti composite anodic oxide films was achieved. The process of hydrolysis precipitation on aluminum was observed by AFM. The time variation in the withstanding voltage of specimens during films dissolution in H_2CrO_4 H_3PO_4 solution was followed. The sputtering time variation in intensity of Al~(3 ) and Ti~(4 ) in composite films was monitored. By dissolution of anodic oxide films and SIMS, Al-Ti composite oxide films are composed of an outer O-enriched Al-Ti composite oxide layer, an intermediate Al-Ti composite oxide layer, and an inner pure Al_2O_3 layer. At the same withstanding voltage of 60V, The capacitance of aluminum foil with Al-Ti composite oxide film was about 51% higher than with pure Al_2O_3 film.