title: A novel Z-scheme BiPO4-Bi2O2(OH)(NO3) heterojunction structured hybrid for synergistic photocatalysis.
abstract: Photocatalysis has been gaining a growing popularity in water treatment, and their engineered applications inspire the development of effective photocatalyst materials. To develop photocatalyst that is effective for degradation of organic pollutants, we fabricate a novel direct solid Z-scheme BiPO4-Bi2O2(OH)(NO3) (BPO-BHN) heterojunction structured hybrid. The results demonstrate an enhanced photocatalytic activity of BPO-BHN to produce OH radicals, according to diffuse reflectance spectroscopy (DRS), electron spin-resonance resonance (ESR), photoelectrochemical measurements, and theoretical calculation results. The BPO-BHN is shown to greatly promote the degradation of 2,4-dichlorophenol (2,4-DCP) under ultraviolet light. On the basis of pseudo-first-order kinetics, the apparent degradation rate constant (kapp) of 0.050 min-1obtained for BPO-BHN is approximately 3.33 and 12.5 times of that for individual BPO (kapp= 0.015 min-1) and BHN (kapp= 0.004 min-1), respectively. This suggests a virtually synergistic photocatalysis of BPO and BHN when they form a direct solid Z-scheme heterojunction structure, which is favorable for improving UV-light harvesting, hole/electron separation and oxidizing capability. In particular, as a novel non-linear optical (NLO) material, the BHN plays a significant role in the formation of Z-scheme structure for its unique ability of capturing photo-electrons from BPO by high-potential C+face in valence band. This study provides a proof-of-concept strategy to develop more effective photocatalysts for degradation of organic pollutants in water.
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China.
authors.forename: Guoshuai
authors.initials: G
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China. Electronic address: sjyou@hit.edu.cn.
authors.forename: Shijie
authors.initials: S
authors.lastname: You
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China.
authors.forename: Hong
authors.initials: H
authors.lastname: Huang
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China.
authors.forename: Ming
authors.initials: M
authors.lastname: Ma
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China.
authors.forename: Nanqi
authors.initials: N
authors.lastname: Ren
mesh_terms: D001729:Bismuth / Q000737:chemistry*; D002384:Catalysis; D002733:Chlorophenols / Q000737:chemistry / Q000528:radiation effects; D007700:Kinetics; D009566:Nitrates / Q000737:chemistry*; D055668:Photochemical Processes; D014466:Ultraviolet Rays; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000528:radiation effects; D018508:Water Purification
chemical_list: D002733:Chlorophenols; D009566:Nitrates; D014874:Water Pollutants, Chemical; C004762:2,4-dichlorophenol; D001729:Bismuth; C035883:bismuth phosphate
keywords: Degradation; Direct solid Z-scheme heterojunction structure; Photocatalysis