[Research of the photoelectrocatalysis degradation of methylene blue of TiO2 nanotube array films annealed in oxygen atmospheres]

Huan Jing Ke Xue. 2011 Nov;32(11):3372-8.
[Article in Chinese]

Abstract

Well-aligned and uniform titanium dioxide nanotube arrays were fabricated in situ on titanium substrate by electrochemical anodic oxidation. SEM images indicate that the TiO2 nanotubes are well organized into high-density uniform arrays,with diameter ranging in size from 70 to 100 nm. The XRD patterns show that the sample fabricated by anodic oxidation is amorphous without being annealed. As the 500 degrees C annealed sample crystallized in the anatase phase, which is in good photocatalytic activity. In quartz glass reactor, the photoelectrocatalytic degradation of MB in aqueous solutions as well as the effect factors and then to 0.1 mol/L NaCl as the electrolyte, under with in oxygen atmospheres annealed the applied bias is 0.5 V and has a pH = 3.25, light intensity is 1 000 microW/cm2 and the surface area of nano-tube array film conditions, will help to improve the TiO2 nanotubes array film photoelectrocatalysis degradation of MB degradation efficiency is 99.56%. The results of EIS analyses revealed that the surface reaction step was the only rate limiting step either for the photoelectrocatalytic process. The extra bias potential could decrease the values of the electron-transfer resistance and increase the separation efficiency of photogenerated electron-hole pairs.

Publication types

  • English Abstract
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Catalysis
  • Electrochemical Techniques
  • Environmental Pollutants / chemistry
  • Environmental Pollutants / isolation & purification
  • Methylene Blue / chemistry*
  • Methylene Blue / isolation & purification
  • Nanotubes / chemistry*
  • Oxygen / chemistry
  • Photochemical Processes*
  • Photolysis*
  • Titanium / chemistry*

Substances

  • Environmental Pollutants
  • titanium dioxide
  • Titanium
  • Oxygen
  • Methylene Blue