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利用Ｒａｍａｎ 激光光谱，ＸＲＤ， ＴＥＭ，ＳＥＭ 和ＵＶＶｉｓ 等手段研究了ＴｉＯ２ 超微粒子的量子尺寸效应与光吸收特性． 结果发现： 由Ｔｉ（ＯＢｕ）４ 在较低ｐＨ 值的水解条件下制得的ＴｉＯ２ 溶胶粒径为５ ～１０ ｎｍ ； 随着热处理温度的升高，ＴｉＯ２ 微粒的粒径增大，经４７３ ～６７３ Ｋ 热处理得到的ＴｉＯ２ 超微粒子粒径为１０ ～２０ ｎｍ ， 呈不规整的锐钛矿型结构．ＴｉＯ２ 的拉曼峰随热处理温度升高而发生红移，表现出量子尺寸效应． 热处理温度升高到８７３ Ｋ 时，粒径增大到３０ ｎｍ 左右，呈锐钛矿型与金红石型混晶结构． 温度进一步升高时，金红石相增多． 由于金红石型ＴｉＯ２ 微粒带隙减小，也使拉曼峰出现红移． 当ＴｉＯ２ 微粒的尺寸明显增大，超出量子尺寸效应范围（２０ ｎｍ）时，其拉曼峰不发生位移． 锐钛矿型ＴｉＯ２ 超微粒子在紫外光区有较好的光吸收性能，并有较高的光催化活性．在较高ｐＨ 值的水解条件下得到的多孔大颗粒ＴｉＯ２ ，对紫外光有散射作用，有效光吸收及光催化降解活性均降低．
The quantum size effect and light absorption properties of TiO2 ultrafine particles were studied by means of Raman laser, XRD, TEM, SEM and UV-Vis. The results showed that the particle size of TiO2 sol was 5 ~ 10 nm with Ti (OBu) 4 hydrolyzed at lower pH value. With the increase of heat treatment temperature, the particle size of TiO2 particles increased, The size of TiO2 ultrafine particles obtained by heat treatment at 673 K is 10 ~ 20 nm, showing an irregular anatase structure. The Raman peak of TiO2 redshifts with the increase of heat treatment temperature, showing the quantum size effect. When the heat treatment temperature is increased to 873 K, the particle size increases to about 30 nm, showing an anatase and rutile mixed crystal structure. When the temperature is further increased, the rutile phase increases. Due to the reduced band gap of the rutile TiO2 particles, the Raman peaks also appear red shift. When the size of TiO2 particles increases obviously beyond the range of quantum size effect (20 nm), the Raman peaks do not shift. Anatase TiO2 ultrafine particles in the UV region has better light absorption properties, and higher photocatalytic activity. The porous large particles of TiO2 obtained under the condition of high pH hydrolysis have the scattering effect on the ultraviolet light, and the effective light absorption and the photocatalytic degradation activity are reduced.