One-step photodeposition of spatially separated CuO x and MnO x dual cocatalysts on g-C 3 N 4 for enhanced CO 2 photoreduction.

The rapid recombination of photogenerated carriers of photocatalysts greatly limits their actual application in CO 2 conversion into valuable chemicals. Herein, dual CuO x and MnO x cocatalysts are decorated on g-C 3 N 4 nanosheets via a one-step photodeposition strategy. Benefiting from the repulsion between Cu 2+ and Mn 2+ cations, a novel g-C 3 N 4 -based heterostructure loaded with spatially separated CuO x and MnO x nanoparticle dual cocatalysts has been successfully fabricated. Cu favors the trapping of electrons, while MnO x tends to collect holes. Moreover, the Cu 2 O/g-C 3 N 4 p-n heterojunction also accelerates the charge separation. As a result, the photogenerated holes and electrons flow into and out of the photocatalyst, respectively, resulting in enhanced charge separation for achieving efficient CO 2 photoreduction over CuO x /g-C 3 N 4 /MnO x . Accordingly, the optimized CuO x /g-C 3 N 4 /MnO x exhibits an improved CO production rate of 5.49 μmol g -1 h -1 , which is 27.5 times higher than that of bare g-C 3 N 4 .