Boosting non-sacrificial H2O2 production on a Bi6S2O15 photocatalyst via creating a crystal surface-dependent internal electric field

Abstract

Photocatalytic H₂O₂ production from H₂O and O₂ is a green technology, but the available photocatalysts are limited, due to multi-step charge transfer-originated recombination. In this work, Bi₆S₂O₁₅ (BSO) photocatalysts exposed with (110), (400), and (−130) surfaces, respectively, are newly studied to produce H₂O₂ from only H₂O and O₂. The crystal surface-dependent internal electric field (IEF) is found to strongly inhibit the rapid charge recombination by generating high charge density at the surface and decreasing the electrostatic potential energy. In particular, BSO with the (110) surface exposed exhibits the highest H₂O₂ production activity (3.4 mM h⁻¹ g⁻¹) under Xe lamp irradiation due to the strongest IEF. The effectiveness of IEF control on H₂O₂ production gives guidelines for developing more efficient photocatalysts in the future.