Acta Phys. -Chim. Sin. ›› 2010, Vol. 26 ›› Issue (03): 663-668.doi: 10.3866/PKU.WHXB20100317

• CATALYSIS AND SURFACE STRUCTURE • Previous Articles     Next Articles

Doping Mechanism of N-TiO2/ZnO Composite Nanotube Arrays and Their Photocatalytic Activity

ZHAI Xiao-Hui, LONG Hui-Jin, DONG Jiang-Zhou, CAO Ya-An   

  1. College of Physics, Nankai University, Tianjin 300071, P. R. China; Teda Applied Physics School, Nankai University, Tianjin 300457, P. R. China
  • Received:2009-08-19 Revised:2009-11-26 Published:2010-03-03
  • Contact: CAO Ya-An E-mail:caoyaan@yahoo.com

Abstract:

TiO2/ZnO and N-doped TiO2/ZnO composite nanotube arrays were synthesized by the sol-gel method using ZnOnanorod arrays as a template. Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and diffuse reflectance UV-Vis spectroscopy (UV-Vis) were used to characterize the samples. The nanotubes had a uniform hexagonal shape. The diameter and wall thickness of the nanotubes were about 100 nm and 20 nm, respectively. Some N dopants were substitutionally doped into the TiO2 lattice, while the N-Ox, N-C, and N-N were chemically absorbed onto the surface of the TiO2/ZnO composite nanotubes. Dopant-induced narrowing of the bandgap resulted from the doping of N ions into the TiO2 lattices. The surface N species enhanced the visible-light response and promoted the separation of photogenerated carriers. Compared with the TiO2/ZnO composite nanotube arrays, the N-TiO2/ZnO composite nanotube arrays exhibited higher photocatalytic activity.

Key words: Photocatalysis, TiO2/ZnO composite nanotube array, N doping, Doping mechanism

MSC2000: 

  • O648