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

• Published in: Nature communications Vol. 10; no. 1; pp. 3844 - 10
• Main Authors: Yang, Deren, Yu, Hongde, He, Ting, Zuo, Shouwei, Liu, Xiaozhi, Yang, Haozhou, Ni, Bing, Li, Haoyi, Gu, Lin, Wang, Dong, Wang, Xun
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 26.08.2019; Nature Publishing Group; Nature Portfolio
• Subjects: 147/137; 147/143; 147/28; 639/301; 639/638; 639/925; Carbon dioxide; Catalysis; Catalysts; Chlorophyll; Copper; Efficiency; Electrocatalysts; Electron transfer; Energy; Energy gap; Gold; Humanities and Social Sciences; Iron; Ligands; Light; Light effects; Metals; Microscopy; Mimicry; multidisciplinary; Nanoparticles; Oxidation; Physics; Science; Science (multidisciplinary); Wavelet transforms
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-019-11817-2

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 CO 2 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. The light field effect can improve performance in electrocatalytic processes, but is not fully understood. Here the authors design a photo-coupled electrocatalyst using a porphyrin ligand as a photosensitizer and a coordinated metal as a catalytically active site for carbon dioxide reduction.