物理化学学报 >> 2005, Vol. 21 >> Issue (10): 1081-1085.doi: 10.3866/PKU.WHXB20051004

研究论文 上一篇    下一篇

Pt、N共掺杂TiO2在可见光下对三氯乙酸的催化降解作用

华南平; 吴遵义; 杜玉扣; 邹志刚; 杨平   

  1. 苏州大学化学系, 苏州 215006; 南京大学环境材料和新型能源研究中心, 南京 210093
  • 收稿日期:2005-01-28 修回日期:2005-04-05 发布日期:2005-10-15
  • 通讯作者: 杨平 E-mail:pyang@suda.edu.cn

Titanium Dioxide Nanoparticles Codoped with Pt and N for Photodegradation of Cl3CCOOH

HUA Nan-ping; WU Zun-yi; DU Yu-kou; ZOU Zhi-gang; YANG Ping   

  1. Department of Chemistry, Suzhou University, Suzhou 215006; Ecomaterials and Renewable Energy Research Center, Nanjing University, Nanjing 210093
  • Received:2005-01-28 Revised:2005-04-05 Published:2005-10-15
  • Contact: YANG Ping E-mail:pyang@suda.edu.cn

摘要: 采用溶胶-凝胶法制备了氮掺杂纳米TiO2(N-TiO2), 并用光分解沉积法在N-TiO2表面负载微量金属Pt(0.5%(w)), 形成铂-氮共掺杂纳米TiO2(Pt/N-TiO2). 实验结果表明, Pt 、N共掺杂纳米TiO2紫外可见光吸收边带较纳米TiO2红移约20 nm, 并在400~500 nm处有弱的吸收. Pt/N-TiO2电极在可见光区的光电流约为纳米TiO2电极的6倍. 以Pt/N-TiO2为催化剂, 催化三氯乙酸(TCA)光降解反应, 室温下经可见光照射2 h后TCA降解率约为8%. N掺杂减小了TiO2的禁带能隙, 使它在可见光区具有光催化活性, 适量Pt掺杂抑制了光生载流子的复合, 加速了电子界面传递速度, Pt、N共掺杂使两种效应相结合, 进一步提高了光催化反应性能.

关键词: 纳米TiO2, Pt、N共掺杂, 三氯乙酸, 可见光, 光催化降解

Abstract: Nanoparticles of titanium dioxide doped with nitrogen (N-TiO2) were synthesized using sol-gel method. Nano-TiO2 codoped with platinum and nitrogen (Pt/N-TiO2) was prepared by photolysis-deposition of H2PtCl6 on N-TiO2 (0.5% (w) Pt). The onset of the absorption spectrum of Pt/N-TiO2 has a 20 nm red-shift and a weak absorption in the wavelength region from 400 to 500 nm compared with the spectrum of the non- doped catalyst. The photocurrent of Pt/N-TiO2 electrode is five times higher than that of TiO2 electrode. The photodegradation yield of trichloroacetic acid over Pt/N-TiO2 catalyst is 8% under visible light irradiation for 2 h. Doping nitrogen in TiO2 reduces the band gap of anatase, which makes N-TiO2 possess catalytic activity in visible light region. Pt clusters precipitated on nano-TiO2 may retard the recombination of the photo-exited charge carriers and improve interfacial charge transfer. Pt/N-TiO2 catalyst benefited from both of the effects.

Key words: Nano-TiO2, Pt and N codoping, Trichloroacetic acid, Visible light, Photodegradation