低温晶化处理对TiO_2纳米管阵列形貌、结构及光电化学性能的影响

Effect of Low-Temperature Crystallization on the Morphology,Microstructure and Photoelectrochemical Property of Anodized TiO_2 Nanotube Arrays

本文通过对所制备的非晶态阳极氧化TiO2纳米管阵列进行水泡、水热以及蒸气热等低温晶化处理,系统考察了低温晶化过程对纳米管阵列形貌、微结构及其模拟太阳光下光电化学性能的影响。研究结果表明:蒸气热处理可促进TiO2纳米管阵列的晶化并保留其管状的形貌特征,最终获得最佳的光电化学性能;水热处理可获得锐钛矿相TiO2,但会使管结构转变为颗粒;水泡处理受水在纳米尺度的管中流动行为的影响,导致管阵列只有管口部分晶化。

This paper describes the crystallization strategy of amorphous TiO2 nanotube arrays prepared by anodization,treated respectively with water soaking,hydrothermal or vapor-thermal treatments.The effects of low-temperature crystallization process on the morphology,microstructures and photoelectrochemical properties of as-prepared TiO2 nanotube arrays were investigated comprehensively.The results showed that vapor-thermal treatment,which was able to remain the tubular morphology,led to an efficient crystallization of amorphous TiO2 nanotube arrays.Thus the highest photoelectrochemical properties were obtained as expected.However,the tubular morphology of amorphous TiO2 nanotube arrays were completely destroyed by the hydrothermal treatment,and only aggregated anatase particles were observed.It was also found that the water soaking resulted in the crystallization of the amorphous TiO2 on the tubular mouth,possibly owing to the limited flow behavior of water in nanoscale-tube during the water soaking process.