Carbon Nitride Photocatalysts with Integrated Oxidation and Reduction Atomic Active Centers for Improved CO2 Conversion

Abstract Single‐atom active‐site catalysts have attracted significant attention in the field of photocatalytic CO 2 conversion. However, designing active sites for CO 2 reduction and H 2 O oxidation simultaneously on a photocatalyst and combining the corresponding half‐reaction in a photocatalytic system is still difficult. Here, we synthesized a bimetallic single‐atom active‐site photocatalyst with two compatible active centers of Mn and Co on carbon nitride (Mn 1 Co 1 /CN). Our experimental results and density functional theory calculations showed that the active center of Mn promotes H 2 O oxidation by accumulating photogenerated holes. In addition, the active center of Co promotes CO 2 activation by increasing the bond length and bond angle of CO 2 molecules. Benefiting from the synergistic effect of the atomic active centers, the synthesized Mn 1 Co 1 /CN exhibited a CO production rate of 47 μmol g −1 h −1 , which is significantly higher than that of the corresponding single‐metal active‐site photocatalyst.