Harnessing In2O3 as an electron aggregator to assist BiOBr nanosheets for enhanced photocatalytic CO2 reduction activity

Abstract

The advancement of catalysts featuring high carrier separation efficiency enhances photocatalytic reduction performance. This study employed a simple hydrothermal method to anchor In2O3 nanoparticles onto the surface of two-dimensional BiOBr nanosheets, constructing a type-II heterostructure that improves the photocatalytic reduction capability. The composites of 0D/2D In2O3/BiOBr underwent XPS, TPR, and MS characterization, validating the formation of a type-II heterostructure. In2O3 functioned as an electron-aggregating active site that extracted photogenerated electrons from the surface of BiOBr. As a result, the efficiency of charge separation is markedly increased. The results of the CO2 reduction test indicate that In2O3-modified BiOBr exhibits superior photocatalytic activity compared to pure BiOBr, with 2 % In2O3/BiOBr exhibiting the highest reduction performance. The CO yield achieved was 9.81 µmol·g−1·h−1, which is 5.33 times higher than that of pure BiOBr and 42.65 times higher than that of pure In2O3. These findings offer future potential for the application of In2O3 as an electron-accumulating material to enable the photocatalytic reduction of CO2.