Electron Transport\nChains Promote Selective Photocatalytic\nConversion of CO<sub>2</sub> to Methanol

The photocatalytic conversion of carbon dioxide (CO<sub>2</sub>) into “liquid sunshine” methanol (CH<sub>3</sub>OH)\nusing semiconductor catalysts has garnered significant attention.\nIncreasing the number of effective electrons and regulating reaction\npathways is the key to improving the activity and selectivity of CH<sub>3</sub>OH. Due to the electron transport properties of semiconductor\nheterojunctions and reduced graphene oxide (rGO), a CoS/CoS<sub>2</sub>-rGO nanocomposite was constructed and applied to the photocatalytic\nreduction of CO<sub>2</sub> to CH<sub>3</sub>OH. The optimized CoS/CoS<sub>2</sub>-rGO-5 photocatalyst achieved a CH<sub>3</sub>OH production\nrate of 15.26 μmol·g<sup>–1</sup> and a selectivity\nof 42%, which were higher than those of CoS and CoS/CoS<sub>2</sub>. This is mainly attributed to the fact that CoS/CoS<sub>2</sub> and\nrGO jointly constructed efficient electron transport chains, which\nnot only ensure that photogenerated electrons can achieve orderly\nand directional migration but also innovatively establish a dual reaction\nsite mechanism, providing strong support for improving photocatalytic\nactivity and selectivity of CH<sub>3</sub>OH. The design of composite\ncatalysts by coupling of semiconductor heterojunctions with carbon\nmaterial affords new territory for efficient photogenerated electron\ntransport and provides alternative pathways for photocatalytic CO<sub>2</sub> conversion.