Hydrogen generation by photoelectrochemical effect of the Cu-doped TiO2 photoanode

Ngoc Tai Ly, Thi Hoa Dao, Le Hong Hoang To, Dinh Lam Vu and Van Hong Le

Abstract

TiO₂ film photoanodes with a size of 1 × 1 cm² were fabricated by a spin coating method. Cu-doped TiO₂ powder with various Cu concentrations (0.2, 0.4, 0.6 and 0.8 at%) and surfactant were used as starting materials in coating Cu-doped TiO₂ thin films onto FTO/glass substrate. Crystalline structure of TiO₂ material, microstructure of the photoanode films and their thickness were identified by x-ray diffraction and Raman scattering. Hydrogen generation from water by photoelectrochemical effect in the visible light was observed by recording I/V characteristics of the photoanode in dark and light regimes. The obtained results have shown that the hydrogen generation efficiency of photoanode nonlinearly depends on Cu concentration. The nonlinear dependence of the hydrogen generation efficiency may be due to a change of resistivity of the film photoanode that is related with the random distribution of the hetero-junction between interfaces of TiO₂ and CuO nanoparticles