BiVO4/Bi2S3 Z-scheme heterojunction with MnOx as a cocatalyst for efficient photocatalytic CO2 conversion to methanol by pure water. (15th December 2022)

• Record Type: Journal Article
• Authors: Wang, Mengyue; Zeng, Shumao; Woldu, Abebe Reda; Hu, Liangsheng
• Is Part Of: Nano energy. Volume 104(2022)Part A
• Publication Date: 2022-12-15
• Subjects: Photocatalytic CO2 reduction -- Internal electric field -- Epitaxial growth -- Z-scheme heterojunction -- In situ XPS; Nanoscience -- Periodicals; Nanotechnology -- Periodicals; Nanostructured materials -- Periodicals; Power resources -- Technological innovations -- Periodicals; Nanoscience; Nanostructured materials; Nanotechnology; Power resources -- Technological innovations; Periodicals; 621.042
• DOI: 10.1016/j.nanoen.2022.107925
• Languages: English
• ISSNs: 2211-2855

Abstract

Abstract: The design of Z-scheme heterostructure is an attractive strategy for efficient charge separation at the interface to boost photocatalytic CO2 reduction. Herein, BiVO4 /Bi2 S3 composite is synthesized through an in situ selective epitaxial growth of Bi2 S3 nanosheets on the (010) facets of BiVO4 . In situ X-ray photoelectron spectroscopy, first-principle simulation, and other characterization tools unveil that the delocalized electrons in Bi2 S3 nanosheets transfer to the BiVO4 within BiVO4 /Bi2 S3 heterostructure, generating an internal electric field (IEF) at the interfaces, directing from Bi2 S3 to BiVO4 . The IEF drives the photoinduced electrons in BiVO4 to Bi2 S3 under light irradiation, establishing direct BiVO4 /Bi2 S3 Z-scheme heterojunction. Moreover, the MnOx cocatalyst is selectively loaded on the (110) facet of BiVO4 by photodeposition. The MnOx /BiVO4 /Bi2 S3 heterostructures convert CO2 to methanol with unity selectivity and stoichiometric O2 production, which is proved by isotopic labeling. This work provides an avenue to design unique heterostructures for CO2 conversion and other applications. Graphical Abstract: The MnOx /BiVO4 /Bi2 S3 heterostructure owns a direct Z-scheme heterojunction that facilitates the photocatalytic reaction by transferring the photogenerated electrons and hole to the Bi2 S3 and MnOx surfaces, thereby catalyzing the CO2 photoreduction into CH3 OH and water oxidation with stoichiometric O2 formation in the absence of a sacrificial agent, respectively. ga1 Highlights: Selective growth of Bi2 S3 nanosheet on the (010) facet of BiVO4 is firstly reported. The in-situ XPS and DFT calculations confirm the Z-scheme charge transfer mechanism. A selective CO2 conversion to CH3 OH with stoichiometric oxygen evolution is reported.