Regulating the interaction between Bi metal and Bi24O31Br10 nanosheets for efficient photoreduction of CO2

Artificial photosynthesis converting CO 2 into valuable compounds has garnered significant interest. However, the insufficient surface activity sites, weak adsorption capacity of CO 2 and poor electron-hole separation capability hinder CO 2 photoreduction used for practical implementation. Herein, Bi nanoparticles/Bi 24 O 31 Br 10 composite photocatalyst (Bi/BOB) was designed constructed through in-situ reduction of bismuth metal on the surface of ultra-thin Bi 24 O 31 Br 10 nanosheets. Bi/BOB exhibits an excellent ability to reduce CO 2 to CO. The CO 2 reduction rate of the optimized Bi/BOB composite catalyst is 43.07 μmol·g −1 ·h −1 , which is significantly superior to other reported bismuth-based photocatalysts. Experimental characterization and Theoretical simulation calculation reveal that the in-situ reduction of bismuth metal causes significant local lattice distortion and uneven charge distribution, thereby producing a strong interaction between Bi nanoparticles and BOB support. So, it enhances the adsorption and activation of carbon dioxide molecules and reduces the Gibbs free energy barrier during the catalytic reaction. Moreover, the strong interaction helps to enhance the separation of photogenerated charge carriers and stability of catalysts. This study offers research suggestions for the interaction between metal and support to enhance CO 2 reduction.