(1. 中南大學(xué) 化學(xué)化工學(xué)院，長沙 410083；2. 中南大學(xué) 有色金屬資源化學(xué)教育部重點(diǎn)實(shí)驗(yàn)室，長沙 410083)
摘 要: 以鈦酸四正丁酯和偏鎢酸銨為原料，采用水熱−模板法制備復(fù)合WO3-TiO2光催化劑。利用X射線衍射(XRD)、掃描電子顯微鏡(SEM)、比表面積(BET)和紫外−可見漫反射(UV-Vis DRS)等手段對催化劑的結(jié)構(gòu)和光學(xué)性能進(jìn)行表征。結(jié)果表明：WO3-TiO2復(fù)合半導(dǎo)體中的TiO2為銳鈦礦晶型，焙燒后的WO3-TiO2呈中空球形結(jié)構(gòu)，粒徑在 320 nm左右，且粒徑分布均勻，其比表面積和平均孔徑分別為40.95 m2/g和16.91 nm, WO3-TiO2復(fù)合半導(dǎo)體的紫外−可見吸收邊帶較TiO2的紅移約50 nm, 并在400~500 nm處有吸收。光降解甲基橙(MO)實(shí)驗(yàn)顯示：經(jīng)過80 min光照后, WO3-TiO2復(fù)合半導(dǎo)體在紫外和可見光下對甲基橙的降解率分別為99.2%和81%，而TiO2的僅為64%和25%，且在紫外和可見光下WO3-TiO2復(fù)合半導(dǎo)體的表觀速率常數(shù)分別是TiO2的3.2和4.9倍左右。
關(guān)鍵字: WO3-TiO2；空心球；水熱−模板法；光降解
（1. School of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China;
2. Key Laboratory of Resources Chemistry of Nonferrous Metals, Ministry of Education,
Central South University, Changsha 410083, China）
Abstract:Composite photocatalysts WO3-TiO2 hollow spheres were prepared by hydrothermal-template method using tetrabutylortitanate and ammonium metatungstate as raw materials. The structural and optical properties of WO3-TiO2 were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), BET analysis and ultraviolet- visible diffuse reflection spectroscopy (UV-Vis DRS). The results show that TiO2 in the WO3-TiO2 hollow spheres is in anatase phase, the calcination of these composite particles results in the fabrication of WO3-TiO2 hollow spheres, the diameter of the composite photocatalysts is about 320 nm with uniform particle size distribution. The specific surface area and average pore diameter of the hollow spheres are 40.95 m2/g and 16.91 nm, respectively. The main absorption edges of the WO3-TiO2 hollow spheres are red-shifted about 50 nm and there is an absorption in the wavelength region from 400 to 500 nm compared with that of the TiO2 hollow spheres. The photodegradation of methyl orange (MO) was used to evaluate the photocatalytic activity of the catalysts under UV and visible light irradiation. 99.2% and 81% MO are degraded by WO3-TiO2 hollow spheres under UV and visible light within 80 min. Under the same conditions, only 64% and 25% MO can be photodegraded by TiO2. The apparent rate constant of WO3-TiO2 composite semiconductor material is significantly increased, which is 3.2 and 4.9 times as that of the TiO2 material under both UV and visible light irradiation, respectively.
Key words: WO3-TiO2; hollow sphere; hydrothermal-template method; photodegradation
