Activity rationalization and mechanism tracking of CO2 photoreduction over 2D-based layered-bismuth-oxyhalides

The layered bismuth oxyhalides (LBO)-based photocatalysts recently delivered exceptional potential in producing valued chemical energy through the photocatalytic CO2 reduction process (PCRP). However, a comprehensive review is lacking which can simultaneously underscore recent activity rationalization and mechanism tracking of LBO-driven PCRP. So, we present a review that uncovers different innovative methods enabling the transitions of physicochemical and optoelectronic properties in LBO-based photocatalysts, leading to efficient PCRP. Wherein particular focus is on accelerating the charge carrier dynamics (e.g., electron/hole separation/ transfer), minimizing the electron/hole recombination, refining the structure/morphology, and ensuring chargelocalized active sites in LBO-based photocatalysts. Specifically, the review began with highlighting the significance of LBO-driven PCRP, its thermodynamical/kinetical aspects, PCRP-associated reaction pathways, PCRP reactor setup, and charge-transferring modes-based division of PCRP. Next, it unravels PCRP activity advancement and in-situ mechanism tracking by depicting exclusive recent examples. Finally, the challenges to LBOdriven PCRP, their solutions, and a feasible future outlook are underlined. This review may offer extendable aspects that could be applied to other materials for driving various redox reactions.