In Situ SERS Monitoring of Plasmon-Mediated Degradation of Microplastics

Microplastics (MPs) are chemically stable and environmentally persistent pollutants that accumulate in natural ecosystems, posing potential risks to both environmental and human health. Despite growing concern, effective strategies for degrading MPs and elucidating their chemical transformations remain limited. In this study, we demonstrate plasmon-mediated degradation of polyethylene (PE) microplastics in aqueous solution using Au nanoparticle clusters (NPCs) under visible light irradiation. Nanogaps within the Au NPCs act as plasmonic hot spots, where hot carriers are generated and utilized in the degradation process, while the enhanced electromagnetic fields enable surface-sensitive detection of chemical changes via surface-enhanced Raman scattering (SERS). By leveraging the integrated catalytic and spectroscopic capabilities of Au NPCs, we conducted real-time SERS monitoring to reveal the plasmon-mediated degradation mechanism of PE MPs.