Synthesis and photocatalytic hydrogen production of a novel photocatalyst LaCO3OH

Abstract

A novel orthorhombic LaCO₃OH photocatalyst is synthesized by a facile hydrothermal method. The prepared LaCO₃OH sample exhibits high photocatalytic activity for hydrogen evolution from aqueous methanol solutions under UV light irradiation, which is about 3 times higher than that of anatase TiO₂. The Mott–Schottky plot shows the V_CB of the prepared LaCO₃OH of −0.87 V vs. RHE at pH 7. Theoretical calculations of the electronic structures for LaCO₃OH reveal that the top of the valence band (VB) and the bottom of the conduction band (CB) are mainly composed of O 2p and La 4f states, respectively. The superior photocatalytic performance of LaCO₃OH could be ascribed predominantly to the high reduction potential of photoinduced electrons. A possible mechanism for the hydrogen evolution over LaCO₃OH is proposed. This work highlights the potential application of lanthanum-based materials in the field of energy conversion.