Carbonized polymer dots modified ultrathin Bi12O17Cl2 nanosheets Z-scheme heterojunction for robust CO2 photoreduction

How to achieve efficient photocatalytic CO2 reduction has received widespread attention. Herein, 0D carbonized polymer dots are evenly loaded on ultrathin 2D Bi12O17Cl2 nanosheets (CPDs/Bi12O17Cl2), which construct the Z-scheme carrier migration system with effectively increased photocatalytic CO2 conversion to CO. The structure and morphology of these samples were investigated by XRD, Raman, XPS, TEM, photocurrent, etc. The reaction mechanism was proposed through in situ FT-IR spectrometry. Under visible light irradiation, the CO evolution rate of 3 wt% CPDs/Bi12O17Cl2 composites is 4.1 times higher than that of pure Bi12O17Cl2 material. The improved photo-reduction CO2 conversion rate of CPDs/Bi12O17Cl2 is ascribed to promoted absorption capacity of visible light, enhanced carrier separation efficiency and increased activity specific surface area. CPDs act as the enrichment center for photo generated electrons in the Z-scheme system and capture sites for CO2, while also strengthen the adsorption and activation of intermediate products COOH*, thereby promoting CO production. (C) 2020 Elsevier Ltd. All rights reserved.

Automated summary

Efficient photocatalytic CO2 reduction has been achieved by evenly loading 0D carbonized polymer dots onto ultrathin 2D Bi12O17Cl2 nanosheets to construct a Z-scheme carrier migration system. This system enhances CO production by promoting visible light absorption, improving carrier separation efficiency, and increasing activity specific surface area. The study provides insights into the mechanisms behind the increased CO2 conversion efficiency.