甘油/DMF混合体系中TiO_2纳米管阵列的制备及表征

Preparation and Characterization of TiO_2 Nanotube Arrays in Glycerin/DMF Mixed Electrolyte

采用电化学阳极氧化法,以甘油/DMF混合溶液为电解质,在纯钛表面制备了一层排列紧密、结构规整的TiO2纳米管阵列。讨论了氧化电压、电解液中DMF比例、电解液中水含量和电解液重复使用对TiO2纳米管阵列形貌的影响,并且从阳极氧化过程中电流-时间曲线出发分析了混合体系中阳极氧化的形成特征。研究表明,氧化电压越高所制备的纳米管管径越大,但是管长与氧化电压之间不呈线性关系;电解液中DMF比例增加不利于纳米管形成;电解液中水含量越高,纳米管管径越大,表面的覆盖物越多,最佳的水含量为1%(体积分数)。经450℃热处理2h后TiO2纳米管阵列的结构由无定形转变为锐钛矿型。

A layer of highly-ordered TiO2 nanotuhe arrays was prepared on the surface of pure titanium through anodization using glycerin/DMF as electrolyte. The influences of oxidation voltage, DMF content of electrolyte, water content of electrolyte and the reuse of electrolyte on the morphology of TiO2 nanotube arrays were discussed, and the electric current during anodic oxidation was monitored to analyze the anodic oxidization formation characteristic. The results showed that, the higher oxidization voltage, the larger the diameter of the prepared TiO2 nanotuhe arrays, but the length of TiO2 nanotube arrays has no linear relationship with the oxidization voltage. Low proportion of DMF suppresses the formation of nanotubes. The diameters of nanotubes rise and more surface covering appear with the increase of water content of electrolyte. The best water content of electrolyte is 1 vol%. The amorphous TiO2 nanotube arrays can be transformed to anatase after annealed at 450 ℃ for 2 h.