Carbon nitride nanosheet-supported CuO for efficient photocatalytic CO 2 reduction with 100% CO selectivity.

The optimal ratio of reaction solutions resulted in excellent performance and product selectivity of CuO/g-C 3 N 4 composites in the photocatalytic CO 2 reduction reaction. A pH-dependent chemical exchange saturation transfer (CEST) imaging nuclear magnetic resonance (NMR) method was used to confirm that CuO modification improves the adsorption capacity of CO 2 .