In-situ formation of Ag2O in metal-organic framework for light-driven upcycling of microplastics coupled with hydrogen production

Abstract

The release of microplastics (MPs) into the environment has engendered considerable ecosystem and human health concerns. Herein, we propose light-driven photocatalytic upcycling of MPs using heterojunction photocatalysts. A novel synthesis method was developed through in-situ conversion of unstable metal sites on bimetallic metal-organic frameworks (MOF), resulting in nanometer-sized particles with semiconductor properties which are confined into the framework of MOFs to prevent agglomeration. These modified MOF can be used for photocatalytic conversion of MPs along with hydrogen (H2) production. As a proof of concept, FeAg-MOF was selected as a precursor to fabricate Ag2O/Fe-MOF photocatalysts. Light illumination induced the formation of Ag2O with a particle size of ∼6 nm into MOF framework structure. The Ag2O/Fe-MOF displays a broad solar light-harvesting range with exposed active sites. Furthermore, band-matching the Ag2O/Fe-MOF heterojunction can enable the conversion of MPs into value-added chemicals, accompanied by H2 production. The present work provides an insight into designing advanced heterojunction photocatalysts and converting MPs into value-added chemicals, coupled with clean energy production.