Photocatalytic Upcycling of Plastic Waste into Syngas by ZnS/Ga2O3 Z-Scheme Heterojunction

Graphical Utilizing solar energy to upcycling plastic waste into value-added chemicals is a promising strategy for realizing sustainable development. In this study, an efficient photocatalytic conversion of polyethylene plastic into syngas (CO+H 2 mixtures) by using a ZnS/Ga 2 O 3 Z-scheme heterojunction photocatalyst is reported. The strategy provides a green approach to effectively mitigate plastic pollution under environmentally friendly conditions. The photocatalytic conversion of plastic waste into value-added products using solar energy presents a promising approach for promoting environmental sustainability. Nonetheless, the emission of CO 2 during the conventional photocatalytic degradation process remains a major hurdle that impedes its further development. In this study, we propose an efficient photocatalytic conversion of polyethylene plastic into syngas (CO+H 2 mixtures) by using a ZnS/Ga 2 O 3 Z-scheme heterojunction photocatalyst. It is found that the strong redox capability of photogenerated holes and electrons in the Z-scheme heterojunction photocatalyst can promote the oxidative depolymerization of PE plastic, concurrently enabling the efficient reduction of the intermediate product CO 2 into syngas. Furthermore, this system also demonstrates applicability in the conversion and upcycling of other polyolefin plastics including polypropylene and polyvinyl chloride. Our findings highlight the potential of polyolefin plastics photoreforming for the production of syngas under environmentally benign conditions.