Fabrication of Fe2O3/TiO2 Photoanode for Improved Photoelectrochemical Water Splitting

A thin layer of TiO2 with photocatalytic property was employed as an interlayer to facilitate electron transfer in a conventional photoanode consisting of Fe2O3 and fluorine-doped tin oxide (FTO) films. The photoelectrochemical performance was compared between the samples with and without the TiO2 interlayer. The photoanode with the interlayer showed a greatly improved performance under 100mW/cm(2) UV-vis light illumination; the onset voltage for the photocurrent shifted to a 20% smaller value of about 0.75 (V vs real hydrogen electrode) and the photocurrent density of 4.35 mA/cm(2) at 1.23 (V vs RHE) was observed, which is 3.5 times larger than that obtained from the photoanode without the TiO2 interlayer. The effect of the TiO2 interlayer on the photoanode performance was systematically investigated, and an effective way to improve the photoanode was suggested. (C) 2013 The Japan Society of Applied Physics