Long-chain hydrocarbons by CO2 electroreduction using polarized nickel catalysts

The electroreduction of CO 2 , driven by renewable electricity, can be used to sustainably generate synthetic fuels. So far, only copper-based materials have been used to catalyse the formation of multicarbon products, albeit limited to C 2 or C 3 molecules. Herein, we disclose that inorganic nickel oxygenate-derived electrocatalysts can generate linear and branched C 3 to C 6 hydrocarbons with sustained Faradaic efficiencies of up to 6.5%, contrasting with metallic nickel, which is practically inactive. Operando X-ray absorption spectroscopy, electrochemical CO stripping and density functional theory pinpoint the presence of stable, polarized Ni δ + active sites associated with Ni–O bonds, which bind CO moderately. The reduction of selected C 1 molecules and density functional theory simulations suggest that the Ni δ + sites promote a mechanism reminiscent of the Fischer–Tropsch synthesis: COOH + CH x coupling followed by successive CH x insertions. Our results disclose atom polarization to be the key that prevents the CO poisoning of nickel and enables CO 2 reduction to a wider pool of valuable products. Cu-based catalysts have dominated CO 2 electroreduction as a result of their unique ability to produce C 2 or C 3 products, while Ni has largely been excluded due to poisoning by intermediate CO. Here, inorganic Ni oxygenate-derived electrocatalysts with polarized Ni δ+ sites can produce multicarbon products, including C 3 to C 6 hydrocarbons.