Photocatalytic Splitting of Liquid Water by n-TiO₂ Suspension

Abstract

By illumination (A >300 nm) of a suspension of n-Ti02 (grain size 5^0.06 mm, 3 to 15 mg/ml) in aqueous acid solutions, containing 10 -3 mol • dm -3 Ce 4+ -ions an enhanced evolution of oxygen is observed. Its yield is dependent on the amount of TiC>2 in the suspension and on the temperature. Using n-TiC>2 suspended in diluted sulfuric acid, hydrogen and oxygen were produced in a ratio of about 2: 1. In both systems n-TiC>2 is acting as an efficient electron donor. For the explanation of the processes probable reaction mechanisms are proposed.