Enhancement of photoelectric catalytic activity of TiO2 film via Polyaniline hybridization

A Polyaniline (PANI)/TiO2 film coated on titanium foil was successfully prepared using the sol-gel method followed by a facile chemisorption. Compared with pristine TiO2, the photocatalytic (PC) and photoelectrocatalytic (PEC) degradation rates of 2,4-dichlorophenol (2,4-DCP) with the PANI/TiO2 film were enhanced by 22.2% and 57.5%, respectively. 2,4-DCP can be mineralized more effectively in the presence of PANI/TiO2 film. The best PEC degradation efficiency of 2,4-DCP with the PANI/TiO2 film was acquired at an external potential of 1.5 V with a layer of 1 nm thick PANI. The PANI/TiO2 film was characterized by Raman spectra, Fourier transform infrared spectra (FT-IR), Auger electron spectroscopy (AES), and electrochemical analysis. These results indicated that there was a chemical interaction on the interface of PANI and TiO2. This interaction may be of significance to promote the migration efficiency of carriers and induce a synergetic effect to enhance the PC and PEC activities. (C) 2011 Elsevier Inc. All rights reserved.