Facets and defects cooperatively promote visible light plasmonic photocatalysis with Bi nanowires@BiOCl nanosheets

Bi nanowires were deposited in situ on BiOCl nanosheets with exposed {001} or {010} facets by reduction of partial Bi3+ on the surface of BiOCl, along with the creation of oxygen defects. In contrast to BiOCl and Ag-deposited BiOCl, Bi@BiOCl displayed enhanced photocatalytic activity and stability for NO removal under visible light irradiation. The surface plasmon resonance of Bi nanowires with different configurations was first simulated with a rigorous Maxwell solver. A significant enhancement of the electric field under visible light irradiation could be observed in the vicinity of the nanowires, and the maximum value of the field intensity was reached at the sharp corners, which behaved as the main active sites for the NO removal reaction. A new visible light photocatalysis mechanism was proposed for the enhanced performance of Bi@BiOCl with plasmonic Bi metal, exposed facets, and oxygen defects. Binanowires-deposited BiOCl with exposed {010} facets exhibited superior photocatalytic activity in comparison with the counterpart with {001} facets, which resulted from higher separation ability of charge carriers and their favorable morphological structure. The present work sheds new light on the photocatalysis mechanism involved with the cooperative effects of surface plasmon resonance (SPR), facets, and defects. As the Bi-based structured materials are abundant, there are numerous opportunities for construction of other high-performance plasmonic photocatalysts based on elemental Bi. (C) 2016 Elsevier Inc. All rights reserved.