Copolymer of Phenylene and Thiophene toward a Visible-Light-Driven Photocatalytic Oxygen Reduction to Hydrogen Peroxide.

ABSTRACT: π-Conjugated polymers including polythiophenes are emerging as promising electrode materials for (photo)electrochemical reactions, such as water reduction to H₂ production and oxygen (O₂) reduction to hydrogen peroxide (H₂O₂) production. In the current work, a copolymer of phenylene and thiophene is designed, where the phenylene ring lowers the highest occupied molecular orbital level of the polymer of visible-light-harvesting thiophene entities and works as a robust catalytic site for the O₂ reduction to H₂O₂ production. The very high onset potential of the copolymer for O₂ reduction (+1.53 V vs RHE, pH 12) allows a H₂O₂ production setup with a traditional water-oxidation catalyst, manganese oxide (MnO _x ), as the anode. MnO _x is deposited on one face of a conducting plate, and visible-light illumination of the copolymer layer formed on the other face aids steady O₂ reduction to H₂O₂ with no bias assistance and a complete photocatalytic conversion rate of 14 000 mg (H₂O₂) g_photocat ^-1 h^-1 or ≈0.2 mg (H₂O₂) cm^-2 h^-1.

SUBMITTER: Oka K 

PROVIDER: S-EPMC7927612 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature