Photocatalytic CO2 reduction of 2D/0D CoAl-LDH@Cu2O catalyst with p-n heterojunction

Zhiyao Wu; Xiyang Wang; Shuang Deng; Xupeng Qin; Qilin Han; Yu Zhou; Yanqiu Zhu; Nannan Wang; Chunlin He; Yimin A Wu

doi:10.1016/j.isci.2023.108435

Photocatalytic CO₂ reduction of 2D/0D CoAl-LDH@Cu₂O catalyst with p-n heterojunction

iScience. 2023 Nov 11;26(12):108435. doi: 10.1016/j.isci.2023.108435. eCollection 2023 Dec 15.

Authors

Zhiyao Wu¹, Xiyang Wang², Shuang Deng¹, Xupeng Qin¹, Qilin Han¹, Yu Zhou¹, Yanqiu Zhu¹, Nannan Wang¹, Chunlin He¹, Yimin A Wu²

Affiliations

¹ State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures, MOE Key Laboratory of New Processing Technology for Nonferrous Metals and Materials, and School of Resources, Environment and Materials, Guangxi University, Nanning 530004, China.
² Department of Mechanical and Mechatronics Engineering, Waterloo Institute for Nanotechnology, Materials Interface Foundry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada.

Abstract

Layered double hydroxides (LDHs) are widely used in catalytic field, especially in photocatalysis, benefiting from the ultrathin 2D structure and luxuriant surface functional groups. However, the wide band gap and low utilization rate of solar spectrum affect their photocatalytic performance. Herein, we integrated n-type CoAl-LDH with p-type Cu₂O nanoparticles to construct a p-n heterojunction with a strong built-in electric field, which can prevent photoinduced electron-hole pairs from recombination as well as facilitate charge transfer. With the X-ray photoelectron spectroscope and in situ Fourier transform infrared spectroscopy, we confirmed the charge transfer under light illumination complying with the type II-scheme mechanism and analyzed the intermediates during photocatalytic CO₂ reduction reaction (CO₂RR). The highest yields reached 320.9 μmol h^-1 g^-1 for CoAl-LDH@Cu₂O-60 (LC-60) under 1 h light irradiation, which was about 1.6 times than the pristine CoAl-LDH. The sample also exhibited excellent stability which maintained 84.1% of initial performance after 4 circulations.

Keywords: energy materials; materials chemistry; optical materials.