Physicochemical properties and photocatalytic H2 evolution activity of Rh-doped La2Ti2O7 prepared by molten salt synthesis

Abstract

La₂Ti₂O₇ doped with Rh showed photocatalytic activity for H₂ evolution from an aqueous methanol solution under visible light irradiation (λ > 420 nm). Molten salt synthesis yielded Rh-doped La₂Ti₂O₇ with a plate-like shape, and a higher crystallinity, phase purity, and visible light absorption capacity than is obtainable using solid state reaction and polymerized complex methods, owing to the photoexcitation of energy levels resulting from the Rh³⁺ doping. These factors led to an increased photocatalytic activity for H₂ evolution after modification with Pt cocatalysts. The effects of the conditions used during molten salt synthesis of Rh-doped La₂Ti₂O₇ on the resultant physical properties and photocatalytic activity are presented.