Soluble polymer microenvironments promote photocatalytic hydrogen peroxide production and self-Fenton reactions

Abstract

Photocatalytic hydrogen peroxide (H₂O₂) production is a promising green technology, but it typically relies on costly sacrificial agents to enhance charge separation and catalytic efficiency. Waste polymers offer a cost-effective alternative, effectively addressing waste management and resource utilization challenges. Herein, we employ waste polymer polyvinyl alcohol (PVA) as a sacrificial agent for photocatalytic H₂O₂ production, avoiding the harsh and complex hydrolysis process of polyesters and polyolefins. Importantly, the unique structure of PVA creates a localized microenvironment with abundant hydroxyl groups, significantly increasing the H₂O₂ yield compared with those of conventional sacrificial agents. Additionally, the introduction of iron ions triggers a photo-self-Fenton (PSF) reaction. The hydroxyl groups on the PVA chain facilitate strong interactions with iron species, thereby enhancing the Fe³⁺/Fe²⁺ redox cycle and enabling the simultaneous removal of both PVA and other pollutants. This approach offers a novel and sustainable pathway for the direct utilization of polymer waste.