The work presents the photo-catalytic reactions of ethanol over Au particles deposited on TiO2 anatase nano- (≤ 10 nm) and micro- (ca. 0.15 μm) particle catalysts. The Au particles are of uniform and similar dimension (mean particle size = ca. 5 nm and 7 nm on the microand nano-sized TiO2, respectively). XPS Au4f indicated that in both cases Au particles are present in their metallic state with no evidence of charge transfer to (or from) the semiconductor. Liquid slurry photoreaction indicated the production of hydrogen with a rate ≈ 2 L/kgCatal.min on 2 wt. % Au/TiO2 anatase nano-particles under UV photo irradiation of comparable intensity to solar radiation. While the reaction rate per unit mass was lower on the micro-sized Au/TiO2 it simply scaled up to an equivalent rate for the nano-sized Au/TiO2 catalyst when normalised by unit area.