Unleashing the Synergistic Potential of 2D-2D Nanosheet Based S-Scheme Heterojunction: Cooperative Boosting of CO Reduction to Solar Fuel and Biomass Valorization.

Harnessing inexhaustible solar energy for CO valorization is a substantial step toward achieving a carbon-neutral energy cycle. However, CO conversion often exhibits slow kinetics, necessitating the utilization of sacrificial agents making the process economically unfeasible. In the ongoing quest for sustainable and economically feasible CO valorization, herein the photoreduction of CO to CO coupled with biomass-based alcohol oxidation to fine chemicals is reported via BiWO/g-CN (BWO/g-CN) 2D-2D nanosheet based S-scheme heterojunction. Importantly, BWO/g-CN-60 exhibits highest photocatalytic activity with CO production rate of 6.87 mmol g h, accompanied by >98 % selectivity and selective oxidation of veratryl alcohol to veratraldehyde, with notable yield of 42 % in 6 h under simulated solar light. The apparent quantum yield (AQY) of 14.3 % is achieved for CO production at the wavelength of 420 nm. Additionally, the formed heterostructure results in enhanced charge separation and accelerated charge transfer kinetics as validated by PL, EIS, and photocurrent studies. EPR, CO labeling DFT studies, and various controlled experiments provided a deeper insight into the mechanism of underlying photo-redox process. Thus, the current study presents a sustainable paradigm for CO mitigation by converting it into solar fuel, while synergistically producing the fine chemicals through effectively harnessing the full potential of charge carriers.