Acta Phys. -Chim. Sin. ›› 2012, Vol. 28 ›› Issue (06): 1489-1496.doi: 10.3866/PKU.WHXB201203221

• CATALYSIS AND SURFACE SCIENCE • Previous Articles     Next Articles

Enhanced Photoeletrocatalytic Activity of TiO2 Nanotube Arrays Modified with Simple Transition Metal Oxides (Fe2O3, CuO, NiO)

CONG Yan-Qing, LI Zhe, WANG Qi, ZHANG Yi, XU Qian, FU Fang-Xia   

  1. College of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310012, P. R. China
  • Received:2012-01-09 Revised:2012-03-21 Published:2012-05-17
  • Contact: CONG Yan-Qing
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (20976162, 21103149, 20906079), Natural Science Foundation of Zhejiang Province, China (R5100266), and Significant Science and Technology Project of Zhejiang Province, China (2010C13001).

Abstract: Composite electrodes consisting of highly ordered, vertically oriented TiO2 nanotube (TiO2-NT) arrays modified with Fe2O3, CuO, and NiO nanoparticles were successfully fabricated by a simple electrochemical anodization and electrodeposition method. Field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and UV-Vis diffuse reflectance spectroscopy were used to characterize the structure and optical properties of the resulting Fe2O3/TiO2-NT, CuO/TiO2-NT, and NiO/TiO2-NT composite electrodes. The photoelectrochemical (PEC) activities of the composite electrodes were evaluated using phenol as a model pollutant. Results indicated that transition metal oxide nanoparticles were deposited on the mouth, tube wall, and base of the TiO2-NTs. The PEC activity of the composite electrodes was over twice that of an unmodified TiO2-NT electrode. The Fe2O3/TiO2-NT electrode showed the highest absorption intensity in the visible light region. After treatment for 120 min, the phenol removal efficiency using the Fe2O3/TiO2-NT anode could reach 96%, while it was only 41% for the unmodified TiO2-NT anode. Moreover, the Fe2O3/TiO2-NT electrode tended to generate intermediates of low toxicity. The higher PEC activity of the composite electrodes was attributed to the presence of hetero-nanostructures with high interfacial area comprised of TiO2-NTs and transition metal oxide nanoparticles, which efficiently facilitated electron transfer and inhibited the recombination of photogenerated electron- hole pairs.

Key words: TiO2 nanotube, Fe2O3, CuO, NiO, Photoelectrocatalysis, Visible light