Direct Z-Scheme Heterojunction of Ligand-Free FAPbBr3/α-Fe2O3 for Boosting Photocatalysis of CO2 Reduction Coupled with Water Oxidation

Yan-Fei Mu; Chao Zhang; Meng-Ran Zhang; Wen Zhang; Min Zhang; Tong-Bu Lu

doi:10.1021/acsami.1c01718

Direct Z-Scheme Heterojunction of Ligand-Free FAPbBr₃/α-Fe₂O₃ for Boosting Photocatalysis of CO₂ Reduction Coupled with Water Oxidation

ACS Appl Mater Interfaces. 2021 May 19;13(19):22314-22322. doi: 10.1021/acsami.1c01718. Epub 2021 May 7.

Authors

Yan-Fei Mu¹, Chao Zhang¹, Meng-Ran Zhang¹, Wen Zhang¹, Min Zhang^{1

2}, Tong-Bu Lu¹

Affiliations

¹ MOE International Joint Laboratory of Materials Microstructure, Institute for New Energy Materials and Low Carbon Technologies, School of Materials Science and Engineering, Tianjin University of Technology, Tianjin 300384, China.
² Tianjin Key Laboratory of Organic Solar Cells and Photochemical Conversion, School of Chemistry and Chemical Engineering, Tianjin University of Technology, Tianjin 300384, China.

PMID: 33961390
DOI: 10.1021/acsami.1c01718

Abstract

Up to now, the majority of the developed photocatalytic CO₂ reduction systems need to use expensive sacrificial reductants as electron source. It is still a huge challenge to drive the photocatalytic CO₂ reduction using water as an electron source. Herein, we report a facile strategy for the construction of direct Z-scheme heterojunction of LF-FAPbBr₃/α-Fe₂O₃, which is manufactured by the in situ and two-step controlled growth of ligand-free formamidinium lead bromide (LF-FAPbBr₃) nanocrystals on the surface of α-Fe₂O₃ nanorods. The matchable energy levels and direct contact between LF-FAPbBr₃ and α-Fe₂O₃ significantly accelerate the interfacial charge transfer, with a charge separation efficiency (η_separation) of 93%, much higher than that of 11% shown by the ligand-capped FAPbBr₃/α-Fe₂O₃ heterojunction. The resulting efficient separation and raised redox ability of photogenerated carriers endow the LF-FAPbBr₃/α-Fe₂O₃ heterojunction with an outstanding photocatalytic performance for CO₂ reduction (to CO and CH₄) coupled with water oxidation (to O₂), achieving a highest electron consumption rate of 175.0 μmol g^-1 h^-1 among the reported metal halide perovskite-based photocatalysts, which are 5 and 11 times higher in comparison with those of sole LF-FAPbBr₃ and ligand-capped FAPbBr₃/α-Fe₂O₃, respectively.

Keywords: CO2 reduction; Z-scheme; artificial photosynthesis; halide perovskite; heterojunction.