Effects of water content and pH on gel-derived TiO2–SiO2
學年 88
學期 1
出版(發表)日期 2000-01-01
作品名稱 Effects of water content and pH on gel-derived TiO2–SiO2
著者 余宣賦; Yu, Hsuan-fu; Wang, Shenq-min
單位 淡江大學化學工程與材料工程學系
出版者 Amsterdam: Elsevier BV * North-Holland
著錄名稱、卷期、頁數 Journal of non-crystalline solids 261(1-3), pp.260-267
摘要 Gel-derived TiO2–SiO2 particles with equal molar compositions and a specific surface area above 300 m2/g were prepared by controlling the molar ratio of H2O to alkoxides at about 10. The effects of molar ratios of H2O/alkoxides, pH of the starting solutions and temperatures of the calcination on the characteristics of the gel-derived TiO2–SiO2 were studied using BET, FT-IR, XRD, SEM and TEM. The results indicated that there was a critical value for H2O/alkoxides molar ratios in all pH conditions to give the highest specific surface areas and pore volumes of the derived specimens. The effects of pH of the starting solutions were not pronounced, in comparison with the effects of H2O/alkoxides molar ratio used. Although the calcination broke Ti–O–Si bonding, at elevated temperatures the mobility of the constituent elements in the structure was not sufficiently high, even at 1123 K, to rearrange the atoms to form the corresponding crystalline phases. Based on the experimental results obtained, three different mechanisms for sol–gel conversion were proposed to explain the effects of H2O/alkoxides molar ratios on the characteristics of gel-derived particles.
關鍵字 S290; S310; T250
語言 en
ISSN 0022-3093
期刊性質 國外
收錄於 SCI EI
國別 NLD
出版型式 紙本

機構典藏連結 ( http://tkuir.lib.tku.edu.tw:8080/dspace/handle/987654321/44184 )