Isolated single atom cobalt in Bi ₃O ₄Br atomic layers to trigger efficient CO ₂ photoreduction

Abstract

The design of efficient and stable photocatalysts for robust CO ₂ reduction without sacrifice reagent or extra photosensitizer is still challenging. Herein, a single-atom catalyst of isolated single atom cobalt incorporated into Bi ₃O ₄Br atomic layers is successfully prepared. The cobalt single atoms in the Bi ₃O ₄Br favors the charge transition, carrier separation, CO ₂ adsorption and activation. It can lower the CO ₂ activation energy barrier through stabilizing the COOH* intermediates and tune the rate-limiting step from the formation of adsorbed intermediate COOH* to be CO* desorption. Taking advantage of cobalt single atoms and two-dimensional ultrathin Bi ₃O ₄Br atomic layers, the optimized catalyst can perform light-driven CO ₂ reduction with a selective CO formation rate of 107.1 µmol g ⁻¹ h ⁻¹, roughly 4 and 32 times higher than that of atomic layer Bi ₃O ₄Br and bulk Bi ₃O ₄Br, respectively.

Abstract

While the conversion of CO ₂ to high-value products provides a promising means to remove and utilize atmospheric carbon, few materials can do so without wasteful, sacrificial reagents. Here, authors prepare single-atom Co on Bi ₃O ₄Br nanosheets as CO ₂ reduction catalysts using water and light.