Promoted photocarriers separation in atomically thin BiOCl/Bi2WO6 heterostructure for solar-driven photocatalytic CO2 reduction

Exploring efficient strategies to promote photocarrier separation remains a challenge in solar energy conversion processes. Herein, we construct a novel atomically thin BiOCl/Bi2WO6 heterostructure to enhance photocarriers separation via the internal electric field at the heterointerface. The resultant atomically thin BiOCl/Bi2WO6 heterostructure exhibits superior photocatalytic CO2 reduction activity with a CH4 evolution rate of ca. 6.63 mu mol g(-1)h(-1) and 82.9% in selectivity under simulated sunlight irradiation without sacrificial reagent. The experimental characterizations highlight that the atomically thin heterostructure endows BiOCl/Bi2WO6 with an enhanced CO2 uptake capability and improved interfacial charge transfer behavior. Further theoretical calculations demonstrate that BiOCl/Bi2WO6 heterointerfaces are energetically more favorable for stabilizing the CHO*, which accounts for the improved photoreduction selectivity of CH4. This work is expected to provide inspiration for preparing other 2D atomically thin heterostructures employed in the solar energy conversion field.

Automated summary

In this study, a novel atomically thin BiOCl/Bi2WO6 heterostructure was constructed to enhance photocarrier separation in solar energy conversion. The resulting heterostructure exhibited superior photocatalytic CO2 reduction activity and selectivity, with improved CO2 uptake capability and interfacial charge transfer behavior. Theoretical calculations further supported the enhanced photoreduction selectivity.