Closing the loop: Waste carbon transformation into solar fuels via CdS/Bi2WO6 heterojunction

The advancement of semiconductor photocatalysis is acknowledged for its prowess as an eco-friendly, energy-efficient, and cost-effective method facilitating diverse organic transformations, including CO 2 photoreduction. Despite its merits, there remains room for enhancing the selectivity and efficiency of these photocatalysts . In this study, we successfully synthesized heterojunction nanocomposites comprising CdS and Bi 2 WO 6 semiconductors to drive the CO 2 -to-methanol conversion, achieving a maximum yield of 9450 μmol/g. Notably, CO (1048 μmol/g) and H 2 (482 μmol/g) were also produced using water within a 16-h photocatalytic period, yielding an average production rate of ∼590 μmol/g-h. Triethylamine played a crucial role by providing electrons to the reaction system. The recovered photocatalyst exhibited consistent performance over five cycles of photoreduction experiments. Various spectroscopic and microscopic techniques were employed to analyze the optical, catalytic, and morphological properties of both the fresh and recovered photocatalysts. The introduced S-scheme heterojunction photocatalyst stands out for its efficient charge carrier separation, enhancing redox capacity, and holds promise as a source for novel strategies to improve the efficiency of CO 2 photoreduction experiments.