载流子分离效率低和光吸收范围窄是制约二氧化钛光催化产氢活性的两个关键因素. 研究表明, 一定浓度的表面缺陷既有利于光生载流子传递到表面缺陷位点, 抑制载流子的复合, 又可以扩展光催化剂的光谱吸收范围, 从而提高光催化活性. 本文利用低成本过渡金属(Co, Ni, Cu和Mn)掺杂在超细二氧化钛表面, 构建了表面缺陷(氧空位和金属阳离子取代缺陷). 相对于原始的缺陷很少的二氧化钛, 表面缺陷的二氧化钛活性可以提升3-4倍, 而且可见光产氢速率高达3.4 μmol/h,在365 nm处的表观量子效率达到36.9%, 这些结果都远远高于商业的P25 TiO2. 我们认为, 光催化产氢活性的明显提升可以归结为更快速的电荷分离和更好的光吸收. 可见, 利用过渡金属进行热液处理来实现表面掺杂是一种非常简便有效构建表面缺陷的方法.%Inefficient charge separation and limited light absorption are two critical issues associated with high-efficiency photocatalytic H2 production using TiO2. Surface defects within a certain concentra-tion range in photocatalyst materials are beneficial for photocatalytic activity. In this study, surface defects (oxygen vacancies and metal cation replacement defects) were induced with a facile and effective approach by surface doping with low-cost transition metals (Co, Ni, Cu, and Mn) on ul-trafine TiO2. The obtained surface-defective TiO2exhibited a 3-4-fold improved activity compared to that of the original ultrafine TiO2.In addition, a H2production rate of 3.4 μmol/h was obtained using visible light (λ > 420 nm) irradiation. The apparent quantum yield (AQY) at 365 nm reached 36.9% over TiO2-Cu, significantly more than the commercial P25 TiO2. The enhancement of photo-catalytic H2production activity can be attributed to improved rapid charge separation efficiency and expanded light absorption window. This hydrothermal treatment with transition metal was proven to be a very facile and effective method for obtaining surface defects.
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