Core–shell Cu@Cu2O nanoparticles embedded in 3D honeycomb-like N-doped graphitic carbon for photocatalytic CO2 reduction

A facile polymer thermal treatment method has been employed to fabricate 3D honeycomb-like nitrogen-doped graphitic carbons (N-GCs) with embedded core–shell Cu@Cu2O nanoparticles (NPs). The 3D honeycomb-like N-GC architectures can not only serve as an excellent carrier for core–shell Cu@Cu2O NPs, but also provide sufficient active sites and fast electron transmission channels. Under visible light irradiation, the Cu@Cu2O/N-GC-600 catalyst has the highest yields of CH4 and CO at 38.89 μmol g−1 and 27.78 μmol g−1, respectively. The excellent photocatalytic activity is attributed to the synergistic effects between the unique N-GC framework and core–shell Cu@Cu2O NPs, which accelerates the transfer of charge carriers and promotes the accumulation of photogenerated electrons on core–shell Cu@Cu2O. The results of this study may be beneficial for the design and synthesis of high-efficiency core–shell photocatalysts.