掺Fe^(3+)附银二氧化钛光催化剂的制备及其光催化活性研究

Preparation and photocatalytic activity of Fe^(3+)-doped and silver-loaded titania photocatalyst

采用酸催化溶胶-凝胶法和光化学沉积法相结合制备出了掺Fe3+附Ag纳米TiO2复合粒子,用TEM、XRD、XPS、UV-vis等技术进行了表征。结果表明:纳米粒子粒径约为10~15nm;Fe3+的掺杂能促进TiO2由锐钛矿相向金红石相的转变;改性后的TiO2对光的吸收发生红移,吸收强度明显增大;XPS分析表明附载在TiO2表面的银以Ag0形式存在。以紫外光为光源,甲基橙为目标降解物,评价了催化剂的光催化活性,实验表明,掺Fe3+附Ag的TiO2比纯TiO2及仅掺Fe3+或仅附Ag的TiO2能显示出更高的光催化活性;且掺Fe3+0.4%、附银1%(摩尔分数)的催化剂的光催化活性最高。

Fe^3＋-doped and Ag-loaded TiO2 nanoparticles were synthesized using acid-catalyzed sol-gel and photodeposition methods. The nanoparticles were characterized by TEM, XRD,XPS and UV-vis techniques. The results showed that the average diameter of nanoparticles was 10~ 15nm. Fe^3＋ doping could promote the phase transformation of TiO2 from anatase to rutile. The absorption of TiO2 nanoparticles with Fe^3＋ doped and Ag loaded to light was red-shifted and the absorption intensities increased evidently. The oxidation state of the silver loaded on the TiO2 was AgO from X-ray photoelectron spectroscopy（XPS）. UV light was used as light source to investigate the photocatalytic activity of the catalyst for the degradation of methyl orange. The results showed that Fe^3＋-doped and Ag-loaded TiO2 exhibited higher photocatalytic activity compared with pure TiO2, Fe^3＋- doped TiO2 as well as Ag-loaded TiO2 ,and the optimal amount of doped Fe^3＋ and loaded Ag was 0.4% and 1% （mole fraction）, respectively.