Tailoring bismuth defects in Bi2WO6 nanosheets for photocatalytic C-H activation

Abstract

Functionalizing sp3 C-H bonds in toluene through photocatalysis poses a significant challenge in organic synthesis, garnering substantial research attention. Nevertheless, the inert nature of the C-H bond restricts the photocatalytic conversion efficiency. Here, we construct bismuth defect modified ultrathin Bi2WO6 nanosheets (BT-48) for the conversion of toluene into benzaldehyde under light irradiation. Density functional theory (DFT) calculations validate the effectiveness of Bi defects in Bi2WO6 in activating the C-H bond in toluene. Moreover, a comprehensive physiochemical analysis shows that the introduction of bismuth defects in ultrathin Bi2WO6 nanosheets could promote the separation of photoexcited charge carriers. As a result, the optimal BT-48 sample exhibits an impressive benzaldehyde formation (6781 μmol g−1 h−1) with a high selectivity of 96%, which is 6 times higher than that of Bi2WO6 (1109 μmol g−1 h−1) and surpasses those of all the previously reported Bi2WO6-based photocatalysts. It is expected that this work could enhance our understanding of designing efficient photocatalysts for the activation of C-H bonds under light illumination.