Ambivalent photocatalytic strategies for plastic waste conversion: Alkalinized carbon nitride for H2O2 production and complete mineralization

Plastic waste poses a significant environmental threat due to its widespread use and disposal, necessitating innovative upcycling methods. Here, we introduce alkalinized carbon nitride (Alk-CN) as an efficient photocatalyst for the solar-driven photoreforming of polyethylene terephthalate (PET) into hydrogen peroxide (H 2 O 2 ) in alkaline environments. Alk-CN also demonstrates versatility for H 2 O 2 production with other polyester-based plastics, including polybutylene terephthalate and polylactic acid . This study pioneers an innovative dual approach to managing PET waste: (i) photoreforming to produce H 2 O 2 and recover TPA from bulk PET waste and (ii) utilizing an AOP system with in-situ generated H 2 O 2 under UV irradiation for the complete mineralization of trace PET waste in wastewater. These findings offer viable strategies for transforming plastic waste into valuable products or achieving complete mineralization, leveraging solar-driven photocatalytic reactions for environmental remediation and resource recovery. • Photoreforming of H 2 O 2 fuel from polyester-based plastics using Alk-CN. • Unveiling crucial insights into the kinetics of H 2 O 2 generation from plastic monomers. • Complete mineralization of PET through photocatalytic AOP using UV 254 irradiation. • Flexibility to control the end-products during photocatalysis of plastic wastes.