Near‐Infrared‐Active Plasmonic S‐Scheme Zn 0.5 Cd 0.5 S/W 18 O 49 Heterojunction Enables Simultaneous Polylactic Acid Photoreforming and Hydrovoltaic Power Generation

ABSTRACT Plastic photoreforming with H 2 evolution offers a sustainable route for waste‐polymer valorization and solar fuel production, but is limited by insufficient separation and utilization of photogenerated charge carriers. Here, a plasmonic Zn 0.5 Cd 0.5 S/W 18 O 49 (ZCS/WO) S‐scheme heterojunction is proposed, in which the localized surface plasmon resonance (LSPR) effect of W 18 O 49 extends the optical response of ZCS/WO into the near‐infrared region and promotes surface reaction kinetics through local photothermal heating and hot‐electron injection, while the S‐scheme heterointerface preserves highly reductive electrons on Zn 0.5 Cd 0.5 S and oxidative holes on W 18 O 49 for efficient polylactic acid (PLA) photoreforming and H 2 evolution. The optimized ZCS/WO achieves an H 2 evolution rate of 37.33 mmol g −1 h −1 and a pyruvate production rate of 35.08 mmol g −1 h −1 , which is 5.74 times higher than that of pristine ZCS. Apparent quantum yields (AQY) of 32.77% and 1.43% at 405 and 810 nm are achieved, respectively. Furthermore, integrating ZCS/WO into a polyacrylamide hydrogel generates a photocatalysis‐enhanced hydrovoltaic device, delivering a voltage up to 0.60 V during PLA photoreforming. This work demonstrates a multifunctional strategy for integrating plastic valorization, solar fuel production and hydrovoltaic electricity generation.