Cobalt single atom induced catalytic active site shift in carbon-doped BN for efficient photodriven CO2 reduction

Active site tuning in catalyst design is the key to improving the catalyst performance. Herein, we introduce single cobalt atoms into carbon-doped boron nitride (C-BN) and find, to our surprise, that the photocatalytic CO 2 reduction site of C-BN shifts from CN 3 to CB 3 . The catalyst Co/C-BN with new active sites exhibits excellent photocatalytic activity and selectivity of CO without adding sacrificial reagents, while the side reaction of hydrogen evolution is significantly inhibited. Theoretical calculations show that the introduced Co atom changes the spin density of the neighboring catalytic site, thus regulating the adsorption energy of the catalytic site for active intermediates (COOH*). Compared with CN 3 site, CB 3 in Co/C-BN shows superiority in CO* formation elementary step for the conversion of CO 2 to CO, and inhibits the generation of adsorbed H 2 in the competitive water-splitting reaction. This work provides valuable insights into the design of highly efficient catalysts in the future.