TiO_2纳米阵列光阳极光电催化水分解研究进展

光电催化水分解制氢是目前解决能源危机与环境污染最理想的技术之一.设计和构筑高效的光阳极是实现光电催化技术实际应用的关键.在众多半导体光阳极材料中,TiO_2纳米阵列由于其快的电荷传输速率,高的光热稳定性,无毒和成本低等优点,已经被广泛用于光电催化水分解反应的研究.但是TiO_2本征的光吸收范围窄、光生电荷复合率高、表面水氧化动力学缓慢严重地制约了其太阳能-氢能转换效率.我们结合近年来国内外及本课题组的研究工作详细论述了TiO_2纳米阵列的改性策略,主要包括利用元素掺杂来拓展TiO_2的光吸收范围并提高导电性,构筑异质结促进光电极电荷的分离与转移,半导体敏化增加光电极的可见光吸收并促进电荷转移,表面处理用于增加表面水氧化反应速率.最后指出了该材料发展现状,并对其发展前景做出展望.我们为进一步提高TiO_2纳米阵列的光电催化水分解活性提供了理论指导和实践借鉴.

Research Advancement of the TiO2 Nanoarrays Photoanode for Photoelectrochemical Water Splitting

Solar-driven photoelectrochemical (PEC) water splitting to produce hydrogen is one of the most ideal strategies for addressing energy crisis and environmental pollution. Designing and constructing high-efficient photoanode is the key to the practical application of PEC technology. Among various photoanodes, due to its fast charge transfer rate, high photothermal stability, non-toxicity and low cost etc, TiO2 nanoarrays has been widely used for the research of PEC water splitting. However, some intrinsic shortcomings of TiO2 including narrow photoabsorption range, high photogenerated charge recombination rate and sluggish oxygen evolution kinetics seriously restrict the solar-to-hydrogen conversion efficiency. In this review, according to the recent research work in our group and other group at home and abroad, we summarize some methods to improve the PEC performance of TiO2 nanoarrays from the aspects of element doping, heterostructure construction, and surface treatment etc. Finally, we point out the existing problems and outlook the direction for future research.