Metal Doping Engineering on ZnCr‐Based Layered Double Hydroxides for Efficient Photocatalytic Valorization of Polyethylene Terephthalate

Abstract The extensive utilization of plastics leads to serious environmental concerns due to their persistence and accumulation in the world. In this study, metal doping engineering over layered double hydroxides (LDHs) is carried out, which is applied to improve photocatalytic performance for upcycling polyethylene terephthalate (PET) into terephthalic acid (TPA) and ethylene glycol (EG). A series of M/ZnCr‐LDHs (M = Ag, Cu, Mo, Ti) is synthesized by co‐precipitation synthesis and subsequent solution plasma treatment. The efficient incorporation of M sites without obviously modifying the LDHs structure is achieved by solution plasma treatment. The investigation reveals that the presence of Ti sites in Ti/ZnCr‐LDHs enhances light absorption, facilitates charge carrier separation, and improves the surface catalytic activity under light irradiation. As a result, Ti/ZnCr‐LDHs display the best performance, achieving complete PET conversion and maximum EG and TPA production of 1215 and 3200 mg gcat ⁻¹ h ⁻¹ , respectively. This work not only provides a universal way for doping engineering over photocatalysts but also provides insight into upcycling plastic waste.