The bare film electrode was found to be unstable during water splitting reactions under illumination of light. Significant improvement of stability was observed for covered , i.e., , thin film electrodes. The , layer also enhanced the rate of oxygen evolution instead of formation, due to its catalytic effect. The highest photoresponse was found with an film prepared at 850°C for 13 min by thermal oxidation. The bandgap energy of both and films was found to be 2.85 eV. X‐ray diffraction results indicate rutile structure for the film. The flatband potential of the film was found to be −1.13 V/saturated calomel electrode from the intercept of the Mott‐Schottky plot. The highest potential‐assisted photoconversion efficiencies, 5.1 and 4.1%, and the corresponding practical photoconversion efficiencies, 2.0 and 1.6%, were obtained for water‐splitting by the and film electrodes, respectively.