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综述了近几年改善TiO2光催化分解水制氢的方法措施。向水中添加供电子物质可减少光生电子与空穴的复合,添加碳酸盐或碘化物有利于光生电子与空穴分离;TiO2表面沉积适量的金属颗粒也有利于实现电子和空穴分离,但沉积太多的金属颗粒不但降低TiO2对光的吸收而且还可能成为光生电荷复合的中心;掺杂合适的金属离子通过形成杂质能级可把TiO2的吸光范围至拓宽可见光,掺杂非金属元素使TiO2的带隙(Eg)变窄,从而使TiO2的吸光红移更明显,但掺杂离子有可能成为光生电荷复合的中心;染料敏化或半导体复合有利于实现电荷分离,提高光电转换效率。将多种修饰方法有机结合起来制取氢是目前的一个研究方向,最后分析了未来的研究重点。
The methods and measures for improving TiO2 photocatalytic decomposition of water to hydrogen in recent years are reviewed. The addition of electron-donating species to water can reduce the recombination of photogenerated electrons and holes, and the addition of carbonate or iodide favors the separation of photogenerated electrons from holes; the deposition of a suitable amount of metal particles on the surface of TiO2 also facilitates the separation of electrons and holes, Deposition of too much metal particles not only reduces the absorption of TiO2 light but also may become the center of photogenerated charge recombination; doping of appropriate metal ions can broaden the visible range of light by doping the energy level of TiO2 to broaden the visible light, doping non-metallic elements The bandgap (Eg) of TiO2 becomes narrower, which makes the redox shift of TiO2 more obvious. However, the doping ions may become the center of photocharge charge recombination. Dye sensitization or semiconductor recombination is conducive to the charge separation and the photoelectric conversion efficiency. It is a current research direction to synthetize many kinds of modification methods to produce hydrogen. Finally, the key points of future research are analyzed.