Facile layer regulation strategy of layered double hydroxide nanosheets for artificial photosynthesis and mechanism insight

CO2 conversion into valuable products by utilizing solar energy is one of the most sustainable approaches to simultaneously address looming energy and environmental issues. Herein, through a facile two-step process, including in-situ inhibiting layer growth and the following 10-min exfoliation process, monolayer NiAl-LDH nanosheet was successfully prepared, which demonstrated electron yield of 18.32 mu mol g-1h 1 and quantum efficiency of 0.09 % in absence of sacrificial agent. The atomic-level dispersed nanosheets enabled the significantly increased carrier density and accelerated carrier separation abilities. In-situ DRIFTS characterization affirmed that the thickness regulation strategy had not only promoted the CO2 adsorption and activation capacity but also altered the adsorption and activation modes of CO2 upon photocatalysts. The ultrathin sample exposed more active sites that were available for binding and activating reactant molecules. More HCO3 - and c-CO(3)2species, the key intermediates to transform into CO2 - active species, were more competitively adsorbed on the ultrathin nanosheets, thus more markedly enhanced photoactivity.