Photoreforming of polyester plastics into added-value chemicals coupled with H₂ evolution over a Ni₂P/ZnIn₂S₄ catalyst

The recycling of plastic waste has attracted increasing attention because of its negative effects on the ecological environment and human health. Photoreforming is emerging as a green and promising approach for upcycling plastic waste into highly valuable chemicals and H₂ fuels. Herein, an earth-abundant Ni₂P/ZnIn₂S₄ catalyst prepared by mechanical grinding is reported to selectively photoreform various polyester plastics into high-added-value chemicals coupled with H₂ evolution under mild conditions. In particular, polylactic acid (PLA) can be upcycled to pyruvic acid (PA) with high activity (745.9 μmol g⁻¹ h⁻¹) and selectivity (>90%). Moreover, the H₂ evolution rate can reach up to 781.3 μmol g⁻¹ h⁻¹ catalyzed by 7.5 wt% Ni₂P/ZnIn₂S₄. This system exhibits excellent photocatalytic performance, benefiting from efficient photogenerated charge carrier separation and transfer between Ni₂P and ZnIn₂S₄. This study provides a viable and promising solution for simultaneously producing high-purity H₂ and added-value chemicals from polyester plastic waste, demonstrating its potential for practical recycling applications.