The discovery of materials for the electrochemical transformation of carbon dioxide into liquid fuels has the potential to impact large-scale storage of renewable energies and reduce carbon emissions. Here, we report the discovery of an electrocatalyst composed of gold nanoparticles on a polycrystalline copper foil (Au/Cu) that is highly active for CO2 reduction to alcohols. At low overpotentials, the Au/Cu electrocatalyst is over 100 times more selective for the formation of products containing C–C bonds versus methane or methanol, largely favouring the generation of alcohols over hydrocarbons. A combination of electrochemical testing and transport modelling supports the hypothesis that CO2 reduction on gold generates a high CO concentration on nearby copper, where CO is further reduced to alcohols such as ethanol and n-propanol under locally alkaline conditions. The bimetallic Au/Cu electrocatalyst exhibits synergistic activity and selectivity superior to gold, copper or AuCu alloys, and opens new possibilities for the development of CO2 reduction electrodes exploiting tandem catalysis mechanisms.

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This material is based on work performed by the Joint Center for Artificial Photosynthesis, a Department of Energy (DOE) Energy Innovation Hub, as follows: the development of electrochemical testing was supported through the Office of Science of the US DOE under award number DE-SC0004993; the development of the gold on copper morphology and the physical characterization of catalysts were supported by the National Science Foundation under grant number 1066515 and by the Global Climate Energy Project at Stanford University. The work of C.G.M.-G. was supported by the Swiss National Science Foundation (grant number P2ELP2_168600). E.R.C. acknowledges support from the National Science Foundation Graduate Research Fellowship under grant number DGE-1147470 and from a Ford Foundation Fellowship. L.W. thanks the Knut and Alice Wallenberg Foundation for financial support. We thank the Stanford NMR Facility and the Stanford Nano Shared Facilities for use of their shared facilities. In particular, we thank T. Carver from the Flexible Cleanroom at the Stanford Nano Shared Facilities for his role in depositing the gold nanoparticles and A. Vailionis at the Stanford Nanocharacterization Laboratory for assistance with the XRD measurements.

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Author notes

  1. These authors contributed equally: Carlos G. Morales-Guio, Etosha R. Cave.


  1. Department of Chemical Engineering, Stanford University, Stanford, CA, USA

    • Carlos G. Morales-Guio
    • , Etosha R. Cave
    • , Stephanie A. Nitopi
    • , Jeremy T. Feaster
    • , Lei Wang
    • , Kendra P. Kuhl
    • , Ariel Jackson
    • , Natalie C. Johnson
    • , David N. Abram
    • , Toru Hatsukade
    • , Christopher Hahn
    •  & Thomas F. Jaramillo
  2. SUNCAT Center for Interface Science and Catalysis, SLAC National Accelerator Laboratory, Menlo Park, CA, USA

    • Christopher Hahn
    •  & Thomas F. Jaramillo


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C.G.M.-G. and E.R.C. synthesized the Au/Cu catalyst and performed the electrochemistry experiments. J.T.F., K.P.K., D.N.A. and T.H. conducted the electrochemistry experiments. L.W. designed and guided the electrochemistry experiments using carbon monoxide. S.A.N. compared the state-of-the-art bimetallic copper catalysts. C.G.M.-G., E.R.C. and L.W. carried out the SEM and XPS experiments. A.J. and N.C.J. performed the TEM experiments. C.G.M.-G. developed the mass transfer mathematical model. All authors analysed the data. T.F.J. and C.H. conceived the project and supervised the research work. C.G.M.-G., E.R.C., C.H. and T.F.J. wrote the manuscript with input from the other authors.

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The authors declare no competing interests.

Corresponding authors

Correspondence to Christopher Hahn or Thomas F. Jaramillo.

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