Sunlight-driven photoelectrochemical water splitting into hydrogen and oxygen presents a great way to develop green solar energy. Titanium dioxide is believed to be one of the most stable photoanode materials. Here, ordered TiO2 nanotube arrays were prepared by anodic oxidation method. Then AgCl or AgBr were successfully de-posited on TiO2 nanotube arrays by dipping method. The morphology and crystal structures of AgX-TiO2 heterojunc-tions were tested by X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM). The results showed that AgCl was deposited with 50 nm thickness and 1μm length structure, while AgBr can be evenly dis-persed on surface of TiO2 nanotube arrays. AgX amount increased with extending impregnation recycling time, and formed different surface morphology of nanotube arrays. Electrochemical test indicated that suitable amount of AgBr in the TiO2nanotube arrays improved the photoelectrochemical properties, an optimum photoconversion efficiency obtained at 2.67%. Excess deposited AgX will lead to incompletely utilizing sunlight due to blocked nanotube arrays, and result in lower photoconversion efficiency.%以阳极氧化法制备的高度有序TiO2纳米管阵列作为基底,用沉积法在TiO2纳米管上复合AgCl和AgBr纳米颗粒形成AgX-TiO2异质结.采用XRD、FESEM等分析结果表征,结果表明:AgCl以厚度为50 nm、长度为1μm的片状结构堆叠分布,AgBr的沉积过程较温和,沉积速度相对更慢,均匀分散在TiO2纳米管表面;随着沉积次数增加,纳米管阵列表面形貌发生改变.光电化学研究表明:样品经过复合AgBr后,可以有效提高TiO2纳米管阵列的光电转化效率,当AgBr沉积1次时,其光电转化效率达到2.67%,而复合的AgCl对于TiO2纳米管阵列的光电效率改善效果欠佳.
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