Constructing electron transport pathway and active sites in Bi and Mo nanoparticles modified Bi24O31Br10 for photocatalytic N2 reduction

Here, the Bi 24 O 31 Br 10 -based composite photocatalysts modified by bimetallic Bi and Mo nanoparticles (NPs) are designed and prepared (Bi-Mo-Bi 24 O 31 Br 10 ). 2D ultra-thin Bi 24 O 31 Br 10 nanosheets with suitable band gap and good chemical and optical stability are selected as the main catalyst to drive N 2 fixation by generating hot carriers. The Bi NPs in the Bi 24 O 31 Br 10 nanosheets serves as a buffer tank for electrons to improve the efficiency of electron transfer. Meanwhile, the Mo NPs serve as catalytic centers for N 2 adsorption and activation, working synergistically to enhance the overall reaction efficiency. Resulting from semiconductor-to-metal −to-metal electron transfer path and the Mo metal adsorption and activation mechanism, the nitrogen fixation rate of the Bi-Mo-Bi 24 O 31 Br 10 photocatalyst is as high as 191.2 μmol g −1 h −1 , and it is 7.2 times compared to pure Bi 24 O 31 Br 10 . This work creates a novel framework for the rational design of highly efficient visible-light-responsive nitrogen fixation catalysts.