Visible-light-switched electron transfer over single porphyrin-metal atom center for highly selective electroreduction of carbon dioxide.

ABSTRACT: External fields are introduced to catalytic processes to improve catalytic activities. The light field effect plays an important role in electrocatalytic processes, but is not fully understood. Here we report a series of photo-coupled electrocatalysts for CO₂ reduction by mimicking the structure of chlorophyll. The porphyrin-Au catalyst exhibits a high turnover frequency of 37,069?h^-1 at -1.1?V and CO Faradaic efficiency (FE) of 94.2% at -0.9?V. Under visible light, the electrocatalyst reaches similar turnover frequency and FE with potential reduced by ~?130?mV. Interestingly, the light-induced positive shifts of 20, 100, and 130?mV for porphyrin-Co, porphyrin-Cu, and porphyrin-Au electrocatalysts are consistent with their energy gaps of 0, 1.5, and 1.7?eV, respectively, suggesting the porphyrin not only serves as a ligand but also as a photoswitch to regulate electron transfer pathway to the metal center.

SUBMITTER: Yang D 

PROVIDER: S-EPMC6710284 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature