Upgraded charge transfer by an internal electric field in 2D/2D BiOCl/N-rich C3N5 heterojunctions for efficiently visible-light catalytic NO removal

Abstract

Construction of internal electric fields by interface engineering is an effective means to upgrade the separation and transfer of photogenerated carriers. Here, 2D/2D BiOCl/C3N5 were developed by growing BiOCl nanosheets in-situ on C3N5 nanosheets using a facile solvothermal method. Characterization and work function analysis prove that an internal electric field is created at the BiOCl/C3N5 interface with the direction from BiOCl to C3N5, which can promote the photogenerated electrons flow from C3N5 to BiOCl. DFT calculations demonstrate that coupling with BiOCl can effectively improve the adsorption and activation of NO and O2 molecules over C3N5 by the more suitable active sites provided by BiOCl. As promoted, the optimum BiOCl/C3N5 exhibited 4.6- and 3.0-times higher activity than C3N5 and BiOCl in photocatalytic air NO removal. Nine cycles of NO degradation experiments proved its excellent stability and reusability. This work provides a strategy for the development of high performance C3N5 based catalysts in addition to demonstrating a new catalyst for air NO removal.