高校地质学报2011，Vol.17Issue(1)：118-124,7.
热处理金红石晶体结构及其光催化活性分析
The Crystal Structure and Photocatalytic Activity of Natural Rutile Modified by Heat Treatment
摘要
Abstract
The micro-structure and photocatalytic activity of natural rutile, which was heated and annealed under hydrogen atmosphere, was studied here. Several conventional mineralogical test methods were used, such as X-ray diffraction (XRD),environmental scanning electron microscopy (ESEM), UV-vis diffusive reflectance absorption spectral analysis and structural refinement using GSAS software with Rietveld method. The natural rutile samples used in this study are found in a metamorphic deposit and collected from Shanxi province, China. The experimental results indicate that V, Fe and other impurities exist in the crystal lattice of natural rutile as isomorphous substitution for Ti ions, which causes distortion of crystal lattice and effectively enhances the photocatalytic activity of the specimens. As the temperature increased, parts of the isomorphous substituted ferric ions were gradually reduced to divalent and elemental iron. On one hand, the unit cell parameters of futile decreased because of escaping of ions from the lattice, which have larger ionic radii than Tin+ ion. On the other hand, the unit cell parameters would be increased because of thermal expansion caused by the heat treatment. Therefore, no significant change in the unit cell parameters was observed. At the same time, the visible light response abilities of heated rutile samples were largely improved with increasing temperature. Compared to the original sample RZM, the light absorption intensity of sample, which was subjected to heat treatment at 900℃, was enlarged by 147.2 ％ at 600 nm. Rietveld refinements suggested that a small amount of simple substance iron appeared when the heating temperature reached 800 ℃ and 900 ℃. Iron is a metallic conductor and has lower Fermi level.When iron was in contact with semiconductor rutile particles, the photo-induced electrons could be transferred rapidly, thereby enhancing the visible light response ability of the system.关键词
天然金红石/氢气热处理/单质铁/可见光响应Key words
natural rutile/ hydrogen heat treatment/ simple substance iron/ visible light response分类
天文与地球科学引用本文复制引用
吴婧,秦善,罗泽敏,庄伟,曾翠平,鲁安怀..热处理金红石晶体结构及其光催化活性分析[J].高校地质学报,2011,17(1):118-124,7.基金项目
国家重点基础研究发展计划(973项目)(2007CB825602) （973项目）
中国地质大学(北京)矿物材料国家专业实验室开放研究基金(09A007)联合资助 （北京）
