离子浓度对TiO_2纳米管阵列的影响

Effect of the Ion Concentration in Electrolyte on the Microstructure of Titania Nanotubes

采用阳极氧化法在纯钛片表面得到了一种规整有序的TiO2纳米管阵列。利用SEM观察纳米管阵列的形貌,用XRD分析其晶型。并考察了阳极氧化电压、Fˉ浓度和溶液的pH值对纳米管阵列形貌和长度的影响。以罗丹明B溶液为目标降解物研究了TiO2纳米管阵列的光催化活性。结果表明,Fˉ浓度不仅影响纳米管阵列的形成时间,而且对纳米管阵列的形貌和长度也有一定的影响;溶液的pH值不仅影响纳米管阵列的长度,在很大程度上也影响纳米管阵列的表面形貌。阳极氧化法制备的TiO2纳米管阵列为无定型,在450℃空气中焙烧2h晶相主要为锐钛矿型TiO2,表现出较好的光催化活性。

The ordered TiO： nanotube arrays were fabricated by anodic oxidation from a pure titanium sheet. The influences of a number of synthesis parameters for the preparation of titanium oxide nanotube such as anodizing potential, the concentration of F^- and H^＋ of the electrolyte have been investigated. The TiO2 nanotube arrays were characterized by XRD and SEM and the photocatalytic activity was characterized by the decomposition of Rhodamine B. The results show that the concentration of F^- and H^＋ of the electrolyte affect not only the length but also the appearance of the TiO2 nanotube arrays. The anodic oxidation TiO2 nanotube arrays were amorphous, but it mainly transformed to be anatase after heat-treating at 450 ℃ for 2 h in air, which have good photocatalytic activity.