结合阳极氧化法、电解法和浸渍法制备了RuO2/TiO2纳米管阵列光催化剂。对纳米管的微观形貌、结构以及表面化学态进行了分析;通过紫外一可见吸收光谱仪分析了浸渍液中钌离子电解前后的变化情况,检测了RuO2/TiO2纳米管阵列在可见光下对亚甲基蓝溶液的光催化性能。结果表明:当电解电压为0.85V时,浸渍液中Ru离子以+2价形式存在;只有当浸渍液中的Ru^3+还原为Ru^3+后,才能负载到TiO2纳米管表面,且煅烧后以RuO2形式均匀分散在TiO2纳米管表面;RuO2/TiO2纳米管仍保持未负载TiO2纳米管的结构特征,且其晶型结构并没有因RuO2的负载而变化,也未增加TiO2纳米管表面羟基数量。最佳浸渍RuCl3溶液浓度为3.0mmol/L,最佳电解电压为0.85V,在此条件下浸渍得到的RuO2/TiO2纳米管阵列的可见光催化活性最佳,光催化降解亚甲基蓝2h的降解率由未负载TiO2纳米管的37.50%提高到66.67%。
RuO2 loaded TiO2 nanotube arrays photocatalyst was fabricated via anodic oxidation, electrolytic method and impregnation method. The morphology, structure and surface chemical states of the nanotubes were analyzed. The change of ruthenium ion in the impregnation solution before and after electrolysis was analyzed by UV-Vis absorption spectroscopy. The photocatalytic properties of RuO2/TiO2 nanotube arrays to methylene blue solution were investigated under visible light irradiation. The results indicate that Ru ion in the impregnating solution exists in +2 valence state at an applying voltage of 0.85 V. Ru element can be only loaded onto the TiO2 nanotubes surface when the Ru^3+ is reduced to Ru^2+ in the impregnation solution, and then formed RuO2 after calcination. RuO2/TiO2 nanotubes are still remained the same structural characteristics as unloaded TiO2 nanotubes, and the crystal structure is not changed after RuO2 loading. The loading of RuO2 cannot cause the increase of the hydroxyl number on the surface of TiO2 nanotubes. The RuO2/TiO2 nanotube arrays with the optimum photocatalytic activity were fabricated in the ruthenium chloride solution with a concentration of 3.0 mmol/L at an electrolytic voltage of 0.85 V. The 2 h visible-light photocatalytic degradation rate of methylene blue increases from 37.50% for pure TiO2 nanotubes to 66.67% for RuO2/TiO2 nanotube arrays.