TiO_2表面包覆SiO_2和Al_2O_3的机理和结构分析  

Mechanism and Structure Analysis of TiO 2 Surface Coated with SiO 2 and Al 2O 3

作　　者：崔爱莉[1] 王亭杰[1] 金涌[1] 肖帅刚[1] 盖旭东[1] 

机构地区：[1]清华大学化工系

出　　处：《高等学校化学学报》1998年第11期1727-1729,共3页Chemical Journal of Chinese Universities

摘　　要：在二氧化钛的表面上包覆一层保护膜，使二氧化钛的表面和周围介质之间产生屏障，从而降低二氧化钛的光化学活性，有利于提高二氧化钛的分散性、耐光性、耐候性和抗粉化性．影响颗粒包膜均匀性和致密性的主要因素是颗粒的分散、加料方式、溶液的酸度和陈化时间等．包膜的均...Photochemical activity of TiO 2 can be reduced through surface coating, which favors to increase dispersiveness, weather resistance and antipulverization. The binary coating process of Si and Al to TiO 2 was studied experimentally. The isoelectic point of TiO 2 in seriflux was measured as pH was equal to 3 6. Maximum Zeta potential can be got at pH 10 around, which favors to dispersion of particles. Studies on the aggregation rate of Si and Al indicate that, when pH has a value between 9 and 10, the aggregation rate of silicon acid is small, which favors to form homogeneous and compact membrane, so optimal coating pH value is between 9 and 10. According to the difference of 2 p orbital electron binding energy of Ti in XPS before and after being coated, it can be inferred that Si and Al in coating layer combine to TiO 2 surface through chemical bond.

关 键 词：二氧化钛 包覆 二氧化硅 钛白粉 氧化铝 保护膜 

分 类 号：TQ134.11[化学工程—无机化工]