A Constructed 2D-Cu2O/Carbon Nitride Heterojunction for Efficient CO2 Photoreduction to CH4

With the dual challenges of global energy scarcity and worsening environmental issues, the efficient and selective conversion of CO2 into CH4-an environmentally friendly fuel with high energy density—offers considerable application potential. In this study, a 2D-Cu2O/carbon nitride (2D-Cu2O/CN) heterojunction catalyst was successfully prepared. Notably, 2D-Cu2O/CN shows enhanced light absorption capacity, reduced charge-transfer resistance, and efficient separation of photogenerated electron–hole pairs. It exhibits a CH4 yield of 14.1 μmol·g−1·h−1, 4-fold higher than that of CN. This study provides a feasible approach for the design of high-efficiency photocatalysts for CO2 reduction to CH4.