Modulating CO₂ Electrocatalytic Conversion to the Organics Pathway by the Catalytic Site Dimension

Electrochemical reduction of carbon dioxide to organic chemicals provides a value-added route for mitigating greenhouse gas emissions. Here, we report a family of carbon-supported Sn electrocatalysts with the tin size varying from single atom, ultrasmall clusters to nanocrystallites. High single-product Faradaic efficiency (FE) and low onset potential of CO₂ conversion to acetate (FE = 90% @ –0.6 V), ethanol (FE = 92% @ –0.4 V), and formate (FE = 91% @ –0.6 V) were achieved over the catalysts of different active site dimensions. The CO₂ conversion mechanism behind these highly selective, size-modulated p-block element catalysts was elucidated by structural characterization and computational modeling, together with kinetic isotope effect investigation.. Authors: Xu, Haiping [Argonne National Laboratory (ANL), Argonne, IL (United States); Northern Illinois University, DeKalb, IL (United States); Northern Illinois University] (ORCID:0000000319300401); Wang, Jianxin [Argonne National Laboratory (ANL), Argonne, IL (United States); Northern Illinois University, DeKalb, IL (United States)] (ORCID:0000000301730577); He, Haiying [Valparaiso University, IN (United States)] (ORCID:0000000234932784); Hwang, Inhui [Argonne National Laboratory (ANL), Argonne, IL (United States)] (ORCID:0000000188851552); Liu, Yuzi [Argonne National Laboratory (ANL), Argonne, IL (United States)] (ORCID:0000000287331683). DOE Contract: AC02-06CH11357; EE0009418. Subjects: 10 SYNTHETIC FUELS; 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Catalysts; Chemical reactions; Ethanol; Metals; Organic compounds