摘要
研究了过渡金属离子、稀土金属离子或N、C阴离子对TiO_2掺杂,以及在氢气氛条件下处理TiO_2,使其具有可见光光催化活性.过渡金属离子掺杂,可在TiO_2晶格中引入缺陷,促进电子-空穴的分离或复合;稀土金属掺杂有利于提高TiO_2的光催化活性,光催化活性的增加可能是由于稀土金属掺杂,增加了TiO_2对污染物的吸附、促进了TiO2红移到较高的波长,以及其表面电子迁移速率的增加阻止了电子-空穴复合;C、N阴离子掺杂或在氢气氛条件下对TiO_2进行处理,可能会产生TiO2-xCx、TiO2-xNx、TiO2-x等半导体,晶体颜色由浅变深,促进对光吸收波长的红移,有利于可见光催化活性的提高.
The investigations on the enhancement of the photocatalytic activity have been undertaken for poly-crystalline TiO2 powders doped with various transition metal ions, rare-earth metals, N and C species, and H2 calcination. Transition metal doped polycrystalline TiO2 can enhance the separation or recombination of electron-hole pairs through inducing structural defects in the titania crystal lattice. Suitable content of doping rare earth metal in TiO2 can efficiently extend the light absorption properties to the visible region. The increase in photoactivity is dominantly due to the higher adsorption, red shifts to a longer wavelength, and the increase in the interfacial electron transfer rate inhibiting electron-hole recombination process. It is concluded that nitrogen or carbon doped, in the part of oxygen-deficient sites, or H2 atmosphere calcined for TiO2 is important to emerge vis-activity. The color of semiconductors formed of TiO2-xCx、 TiO2-xNx 、TiO2-x changes from shallow to beige color, which enhances red shifts to a light absorption wavelength for that of TiO2 and improves the photo-catalytic activity.
出处
《哈尔滨工业大学学报》
EI
CAS
CSCD
北大核心
2005年第1期95-97,119,共4页
Journal of Harbin Institute of Technology
基金
国家自然科学基金资助项目(50478065)安徽省优秀青年科技基金资助项目(2001-35).
