催化学报

催化学报 ›› 2012, Vol. 33 ›› Issue (8): 1395-1401.DOI: 10.3724/SP.J.1088.2012.20353

• 研究论文 • 上一篇    下一篇

P 掺杂量对纳米 TiO2 结构及其光催化甘油水溶液制氢性能的影响

田野1, 桑换新1,2, 王希涛2,*   

  1. 1天津市环境保护科学研究院, 天津 300191; 2天津大学化工学院, 天津 300072
  • 收稿日期:2012-03-30 修回日期:2012-05-26 出版日期:2012-08-01 发布日期:2012-08-01

Effects of P Doping Amount on Structure and Photocatalytic Performance of TiO2 for H2 Production from Glycerol Solution

TIAN Ye1, SANG Huanxin1,2, WANG Xitao2,*   

  1. 1Tianjin Academy of Environmental Sciences, Tianjin 300191, China; 2College of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
  • Received:2012-03-30 Revised:2012-05-26 Online:2012-08-01 Published:2012-08-01

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摘要： 以钛酸丁酯为前驱体, 以 NaH2PO4 为掺杂离子给体, 采用溶胶-凝胶法制备了系列 P 掺杂的 TiO2 光催化剂, 运用 N2 吸附-脱附、透射电子显微镜、X 射线衍射、傅里叶变换红外吸收光谱、激光拉曼光谱、紫外-可见光漫反射等技术对催化剂进行了表征. 结果表明, 适量掺杂的 P 可以进入 TiO2 骨架中, 而掺杂量过高时, P 将溶解于 TiO2 晶格间隙中; P 掺杂后的 TiO2 均为具有介孔结构的锐钛矿晶型纳米颗粒, 其晶粒变小, 分散度明显提高. 适量 P 掺杂增大样品的比表面积, 并使得 TiO2 禁带内引入杂质能级, 降低了禁带能量, 增加了光生电子和空穴的分离性能, 提高了 TiO2 的吸光性能. 光催化甘油水溶液制氢反应结果表明, P 掺杂的 TiO2 表现出远高于纯 TiO2 的光催化活性; 5%P 掺杂样品在紫外光和模拟太阳光辐射下, 其最高产氢速率可分别达 1838 和 209 μmol/(g•h). 这与掺 P 后晶粒变小、比表面积增大、禁带能量降低以及光生电子和空穴的分离性能增加有关.

Abstract:  Using tetrabutyl-titanate and sodium dihydrogen phosphate as raw materials, TiO2 and P5+-doped TiO2 semiconductors were prepared by the sol-gel method. Their pore distribution, crystal structure, surface compositions, and photoabsorption properties were investigated by N2 adsorption-desorption, X-ray diffraction, Fourier transform infrared spectroscopy, FT-Raman, transmission electron microscopy and UV-Vis diffuse reflectance spectrum. The results show that P5+-doped TiO2 exists in nano-particles of anatase phase with mesoporous structure. P5+-doped TiO2 samples exhibit much smaller crystallite size and much higher specific surface area than pure TiO2. P-doped TiO2 samples show an extension of light absorption into the visible region, which mainly originates from the doping process with the formation of new energy level of P5+ between conductor band and valence band of TiO2 to reduce the energy gap and the electron-hole recombination rate. The P5+-doped TiO2 samples display improved photocatalytic activity for H2 production from glycerol solution, and 5% P5+-doped TiO2 shows a maximum H2 production rate of 1838 μmol/(g·h) under UV irradiation and 209 μmol/(g·h) under simulated-solar irradiation, respectively, which is related to the decrease of crystal particles, increase of specific surface area, and the reduce of the energy gap and the electron-hole recombination rate.

Key words: phosphorus, doping, titanium dioxide, nano-particle, photocatalysis, glycerol solution, hydrogen production