Interfacial activation of reactants and intermediates on CaSO4 insulator-based heterostructure for efficient photocatalytic NO removal

Abstract

The interfacial structure plays a key role for photoinduced charge transfer and molecular activation in heterogenous photocatalysis. However, the specific interfacial electronic structure of heterostructure and its effect on the photocatalysis reaction have remained unclear. Herein, insulator-based heterostructure (CaSO4-BiOI) was constructed to investigate the atomic interfacial structure. The interface in CaSO4-BiOI heterostructure presents electron-rich environment which could enhance the electronic interaction between catalyst surface and reactants, and thus promotes activation and dissociation of reactants. Taking photocatalytic NO oxidation as target reaction, the adsorption-reaction process was dynamically monitored by in situ DRIFT and plenty of reaction intermediates were observed. The generation of new activated molecules and intermediates could provide an alternative pathway to enhance the conversion of inert pollutant. Hence, the reactants and intermediates can be smoothly converted to the final products with the assistance of electron-rich environment at the interface of heterostructure, achieving the safe and efficient photocatalytic performance.