Opening Direct Electrochemical Fischer-Tropsch Synthesis Path by Interfacial Engineering of Cu Electrode with P-Block Elements

The electrochemical synthesis of syngas (CO and H₂) has garnered considerable attention in the context of Fischer-Tropsch (FT) synthesis employing thermal catalysts. Nonetheless, the need for a novel, cost-effective technique persists. In this investigation, we introduce a direct electrochemical (dEC) approach for FT synthesis that functions under ambient conditions by utilizing a p-block element (Sn and In) overlaid Cu electrode. Surface *CO and H* species were obtained in an electrolytic medium through the CO₂ + H⁺ + e^- → HOOC_ad → *CO (or direct CO adsorption) and H⁺ + e^- → H* reactions, respectively. We have observed C_2-7 long-chain hydrocarbons with a C_nH_2n+2/C_nH_2n ratio of 1-3, and this observation can be explained through the process of C-C coupling chain growth of the conventional FT synthesis, based on the linearity of the Anderson-Schulz-Flory equation plots. Thick Sn and In overlayers resulted in the dominant production of formate, while CO and C₂H₄ production were found to be proportional and inversely correlated to H₂, C₂H₆, and C_3-7 hydrocarbon production. The EC CO₂/CO reduction used in dEC FT synthesis offers valuable insights into the mechanism of C₂₊ production and holds promise as an eco-friendly approach to producing long-chain hydrocarbons for energy and environmental purposes.