第六讲：二氧化钛基光电催化材料制备与性能研究.pdf

二氧化钛及其催化材料的结构与性能 一、二氧化钛的结构 • 二氧化钛的3种晶体结构： • 金红石 • 锐钛矿 • 板钛矿 • 三种晶相的晶体结构的基本结构单元为 [TiO6]八面体。 1 板钛矿 2 锐钛矿 3 金红石 • 三种晶相的晶体结构以[TiO ]八面体共棱为基础的； 6 • 差别在于每个[TiO ]八面体与其它[TiO ]八面体共 6 6 棱的数目不同： • 金红石为2 ； • 板钛矿为3 ； • 锐钛矿为4 。 4 金红石的横切 面结构示意图 5 金红石晶胞结构示意图 Green: Chlorine Grey: Titanium Red: Oxygen Greyish white: Hydrogen 6 金红石晶胲结构示意图 7 Preparation of rutile nanoparticle The fabrication process could be divided into two steps: the preparation of TiCl4 aqueous sol ； the hydrolysis of TiCl4 aqueous solution at 90 ℃. The first step, commercial titanium tetrachloride (98%, TiCl4, Shanghai Chemical Agent Company.) was used as the starting material without further purification. Titanium tetrachloride liquid was added dropwise into a 300 mL of deionized water, while keeping the mixing course under stirring and the system at the temperature below 40 ℃in an ice-water bath. After titanium tetrachloride had been added, the mixture liquid was stirred for another 2 hours, and then cooled down to room temperature. The second step the above aqueous sol was added 12 hours latter into a three-necked flask, and 100 mL of deionized water was added dropwise into the flask while stirring. The flask was fixed in an ice-water bath to keep the temperature of the mixture liquid below 40 ℃. After deionized water had been added, the system was under stirring for another 30 minutes, the temperature of the mixture was raised to 60 ℃ and stirre