粉末TiO_2光催化剂暴露晶面结构  

Investigation on Real Powdery TiO_2 Photocatalyst by Selected Area Diffraction

作　　者：王发扬[1] 翁玉攀 林良牧 

机构地区：[1]厦门大学分析测试中心 [2]厦门大学化学系

出　　处：《厦门大学学报（自然科学版）》1989年第1期53-57,共5页Journal of Xiamen University：Natural Science

摘　　要：用透射式电子显微镜选区电子衍射法,直接观测粉末状TiO_2光催化剂的暴露晶面结构。从原子水平解释了锐钛矿型和金红石型,TiO_2的这两种同素异构体的光催化活性不同的原因,实验证明,锐钛矿型比金红石型光催化活性较高,其原因是前者的暴露晶面应是高的台阶密度、并且其基面结构与反应物匹配对应,作者认为,作为研究工具,SAD有较LEED的延伸和补充。Almost.a1 solidery catalysts are in powdery state, but the theo ries on surface structure of beterogeneous catalysis are mainly from the re-sults of observation of bulky single crystal. For example, determination of the surface structure by low encrgy electron diffraction (LEED) requires single crystal surfaces only.In this paper, powdery TiO2 photocatalysts were examin ed directly by selected area diffraction (SAD) technique in a transmissior electron microscope. It was concluded that two fectors, namely the density of steps and the geometrical symmetry of surface structure, are both playing important roles in photocatalysis. The experiment attempted to establish ; way in which the powdery catalyst can be studied directly in atomic scale.

关 键 词：选区电子衍射 暴露晶面结构 

分 类 号：O614.411[理学—无机化学]