Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Electroreduction of carbon monoxide to liquid fuel on oxide-derived nanocrystalline copper

Subjects

Abstract

The electrochemical conversion of CO2 and H2O into liquid fuel is ideal for high-density renewable energy storage and could provide an incentive for CO2 capture. However, efficient electrocatalysts for reducing CO2 and its derivatives into a desirable fuel1,2,3 are not available at present. Although many catalysts4,5,6,7,8,9,10,11 can reduce CO2 to carbon monoxide (CO), liquid fuel synthesis requires that CO is reduced further, using H2O as a H+ source. Copper (Cu) is the only known material with an appreciable CO electroreduction activity, but in bulk form its efficiency and selectivity for liquid fuel are far too low for practical use. In particular, H2O reduction to H2 outcompetes CO reduction on Cu electrodes unless extreme overpotentials are applied, at which point gaseous hydrocarbons are the major CO reduction products12,13. Here we show that nanocrystalline Cu prepared from Cu2O (‘oxide-derived Cu’) produces multi-carbon oxygenates (ethanol, acetate and n-propanol) with up to 57% Faraday efficiency at modest potentials (–0.25 volts to –0.5 volts versus the reversible hydrogen electrode) in CO-saturated alkaline H2O. By comparison, when prepared by traditional vapour condensation, Cu nanoparticles with an average crystallite size similar to that of oxide-derived copper produce nearly exclusive H2 (96% Faraday efficiency) under identical conditions. Our results demonstrate the ability to change the intrinsic catalytic properties of Cu for this notoriously difficult reaction by growing interconnected nanocrystallites from the constrained environment of an oxide lattice. The selectivity for oxygenates, with ethanol as the major product, demonstrates the feasibility of a two-step conversion of CO2 to liquid fuel that could be powered by renewable electricity.

Your institute does not have access to this article

Relevant articles

Open Access articles citing this article.

Access options

Buy article

Get time limited or full article access on ReadCube.

$32.00

All prices are NET prices.

Figure 1: Physical characterization of Cu nanoparticle and OD-Cu electrodes.
Figure 2: Comparison between OD-Cu 1, OD-Cu 2 and Cu nanoparticle electrodes in electrolyses performed in 0.1 M KOH saturated with 1 atm CO at ambient temperature.
Figure 3: Comparison of CO reduction in 0.1 M KOH saturated with 1 atm of CO versus 2.4 atm of CO.

References

  1. Appel, A. M. et al. Frontiers, opportunities, and challenges in biochemical and chemical catalysis of CO2 fixation. Chem. Rev. 113, 6621–6658 (2013)

    CAS  Article  Google Scholar 

  2. Jhong, H. R., Ma, S. & Kenis, P. J. A. Electrochemical conversion of CO2 to useful chemicals: current status, remaining challenges, and future opportunities. Curr. Opin. Chem. Eng. 2, 191–199 (2013)

    Article  Google Scholar 

  3. Cole, E. B. & Bocarsly, A. B. in Carbon Dioxide as Chemical Feedstock (ed. Aresta, M.) 291–316 (Wiley, 2010)

    Book  Google Scholar 

  4. Costentin, C., Robert, M. & Saveant, J. M. Catalysis of the electrochemical reduction of carbon dioxide. Chem. Soc. Rev. 42, 2423–2436 (2013)

    CAS  Article  Google Scholar 

  5. Benson, E. E., Kubiak, C. P., Sathrum, A. J. & Smieja, J. M. Electrocatalytic and homogeneous approaches to conversion of CO2 to liquid fuels. Chem. Soc. Rev. 38, 89–99 (2009)

    CAS  Article  Google Scholar 

  6. Costentin, C., Drouet, S., Robert, M. & Saveant, J. M. A local proton source enhances CO2 electroreduction to CO by a molecular Fe catalyst. Science 338, 90–94 (2012)

    CAS  ADS  Article  Google Scholar 

  7. Hori, Y. in Modern Aspects of Electrochemistry Vol. 42 (eds Vayenas, C. G., White, R. E. & Gamboa-Aldeco, M. E.) 89–189 (Springer, 2008)

    Book  Google Scholar 

  8. Chen, Y., Li, C. W. & Kanan, M. W. Aqueous CO2 reduction at very low overpotential on oxide-derived Au nanoparticles. J. Am. Chem. Soc. 134, 19969–19972 (2012)

    CAS  Article  Google Scholar 

  9. Tornow, C. E., Thorson, M. R., Ma, S., Gewirth, A. A. & Kenis, P. J. A. Nitrogen-based catalysts for the electrochemical reduction of CO2 to CO. J. Am. Chem. Soc. 134, 19520–19523 (2012)

    CAS  Article  Google Scholar 

  10. DiMeglio, J. L. & Rosenthal, J. Selective conversion of CO2 to CO with high efficiency using an inexpensive bismuth-based electrocatalyst. J. Am. Chem. Soc. 135, 8798–8801 (2013)

    CAS  Article  Google Scholar 

  11. Ebbesen, S. D. & Mogensen, M. Electrolysis of carbon dioxide in solid oxide electrolysis cells. J. Power Sources 193, 349–358 (2009)

    CAS  ADS  Article  Google Scholar 

  12. Hori, Y., Takahashi, R., Yoshinami, Y. & Murata, A. Electrochemical reduction of CO at a copper electrode. J. Phys. Chem. B 101, 7075–7081 (1997)

    CAS  Article  Google Scholar 

  13. Hori, Y., Murata, A., Takahashi, R. & Suzuki, S. Electroreduction of CO to CH4 and C2H4 at a copper electrode in aqueous solutions at ambient temperature and pressure. J. Am. Chem. Soc. 109, 5022–5023 (1987)

    CAS  Article  Google Scholar 

  14. Gattrell, M., Gupta, N. & Co, A. A review of the aqueous electrochemical reduction of CO2 to hydrocarbons at copper. J. Electroanal. Chem. 594, 1–19 (2006)

    CAS  Article  Google Scholar 

  15. Hori, Y., Takahashi, I., Koga, O. & Hoshi, N. Selective formation of C2 compounds from electrochemical reduction of CO2 at a series of copper single crystal electrodes. J. Phys. Chem. B 106, 15–17 (2002)

    CAS  Article  Google Scholar 

  16. Calle-Vallejo, F. & Koper, M. T. M. Theoretical considerations on the electroreduction of CO to C2 species on Cu(100) electrodes. Angew. Chem. Int. Ed. 52, 7282–7285 (2013)

    CAS  Article  Google Scholar 

  17. Schouten, K. J. P., Qin, Z. S., Gallent, E. P. & Koper, M. T. M. Two pathways for the formation of ethylene in CO reduction on single-crystal copper electrodes. J. Am. Chem. Soc. 134, 9864–9867 (2012)

    CAS  Article  Google Scholar 

  18. Kuhl, K. P., Cave, E. R., Abram, D. N. & Jaramillo, T. F. New insights into the electrochemical reduction of carbon dioxide on metallic copper surfaces. Energy Environ. Sci. 5, 7050–7059 (2012)

    CAS  Article  Google Scholar 

  19. Hori, Y., Murata, A. & Takahashi, R. Formation of hydrocarbons in the electrochemical reduction of carbon dioxide at a copper electrode in aqueous solution. J. Chem. Soc. Faraday Trans. I 85, 2309–2326 (1989)

    CAS  Article  Google Scholar 

  20. Li, C. W. & Kanan, M. W. CO2 reduction at low overpotential on Cu electrodes resulting from the reduction of thick Cu2O films. J. Am. Chem. Soc. 134, 7231–7234 (2012)

    CAS  Article  Google Scholar 

  21. Gileadi, E. Electrode Kinetics for Chemists, Engineers, and Materials Scientists Ch. 1 1–8 (Wiley, 1993)

    Google Scholar 

  22. Hori, Y., Murata, A. & Yoshinami, Y. Adsorption of CO, intermediately formed in electrochemical reduction of CO2, at a copper electrode. J. Chem. Soc. Faraday Trans. 87, 125–128 (1991)

    CAS  Article  Google Scholar 

  23. Montoya, J. H., Peterson, A. A. & Nørskov, J. K. Insights into C–C coupling in CO2 electroreduction on copper electrodes. ChemCatChem 5, 737–742 (2013)

    CAS  Article  Google Scholar 

  24. Koga, O. et al. Infrared spectroscopic and voltammetric study of adsorbed CO on stepped surfaces of copper monocrystalline electrodes. Electrochim. Acta 50, 2475–2485 (2005)

    CAS  Article  Google Scholar 

  25. Shaw, S. K. et al. Role of axially coordinated surface sites for electrochemically controlled carbon monoxide adsorption on single crystal copper electrodes. Phys. Chem. Chem. Phys. 13, 5242–5251 (2011)

    CAS  Article  Google Scholar 

  26. Radetic, T., Lancon, F. & Dahmen, U. Chevron defect at the intersection of grain boundaries with free surfaces in Au. Phys. Rev. Lett. 89, 085502 (2002)

    CAS  ADS  Article  Google Scholar 

  27. Wang, S. Y., Jiang, S. P., White, T. J., Guo, J. & Wang, X. Electrocatalytic activity and interconnectivity of Pt nanoparticles on multiwalled carbon nanotubes for fuel cells. J. Phys. Chem. C 113, 18935–18945 (2009)

    CAS  Article  Google Scholar 

  28. Gavrilov, A. N. et al. On the influence of the metal loading on the structure of carbon-supported PtRu catalysts and their electrocatalytic activities in CO and methanol electrooxidation. Phys. Chem. Chem. Phys. 9, 5476–5489 (2007)

    CAS  Article  Google Scholar 

  29. Mills, G. A. Status and future opportunities for conversion of synthesis gas to liquid fuels. Fuel 73, 1243–1279 (1994)

    CAS  Article  Google Scholar 

  30. Gupta, M., Smith, M. L. & Spivey, J. J. Heterogeneous catalytic conversion of dry syngas to ethanol and higher alcohols on Cu-based catalysts. ACS Catal. 1, 641–656 (2011)

    CAS  Article  Google Scholar 

  31. Waszczuk, P., Zelenay, P. & Sobkowski, J. Surface interaction of benzoic-acid with a copper electrode. Electrochim. Acta 40, 1717–1721 (1995)

    CAS  Article  Google Scholar 

  32. CRC. Handbook of Chemistry and Physics 9th edn, section 5 (CRC, 2013).

Download references

Acknowledgements

We thank Stanford University and the NSF (CHE-1266401) for support of this work. C.W.L. gratefully acknowledges an NSF Predoctoral Fellowship. A portion of this work was performed at NCEM, which is supported by the Office of Science, Office of Basic Energy Sciences of the US Department of Energy under contract number DE-AC02-05CH11231. We thank M. Toney and B. Shyam for assistance with grazing incidence X-ray diffraction performed at SSRL, a national user facility operated by Stanford University on behalf of the Office of Basic Energy Sciences of the US Department of Energy.

Author information

Authors and Affiliations

Authors

Contributions

C.W.L. and M.W.K. designed the experiments. C.W.L. prepared and characterized all electrodes and performed all electrochemical experiments; J.C. obtained all TEM images; C.W.L. and M.W.K. wrote the manuscript. All authors contributed to the overall scientific interpretation and edited the manuscript.

Corresponding author

Correspondence to Matthew W. Kanan.

Ethics declarations

Competing interests

C.W.L. and M.W.K. have filed a patent application (WO 2013-US25791, US) covering oxide-derived Cu and other oxide-derived catalysts for electrochemical fuel synthesis.

Extended data figures and tables

Extended Data Figure 1 Additional physical characterization of OD-Cu 1.

a, X-ray photoelectron spectroscopy survey spectrum. b, High-resolution X-ray photoelectron spectrum of the Cu LMM region. c, High-resolution X-ray photoelectron spectrum of the Cu 2p peaks. d, Low-resolution SEM image.

Extended Data Figure 2 Additional physical characterization of OD-Cu 2.

a, X-ray photoelectron spectroscopy survey spectrum. b, High-resolution X-ray photoelectron spectrum of the Cu LMM region. c, High-resolution X-ray photoelectron spectrum of the Cu 2p peaks. d, Low-resolution SEM image.

Extended Data Figure 3 Additional physical characterization of Cu nanoparticle electrodes.

a, X-ray photoelectron spectroscopy survey spectrum. b, High-resolution X-ray photoelectron spectrum of the Cu LMM region. c, High-resolution X-ray photoelectron spectrum of the Cu 2p peaks. d, Low-resolution SEM image.

Extended Data Figure 4 Additional grazing-incidence X-ray diffraction pattern data, collected using synchrotron X-rays at 11.5 keV.

a, X-ray diffraction patterns for OD-Cu 1 and OD-Cu 2. b, c, Williamson–Hall plots for OD-Cu 1 (b) and for OD-Cu 2 (c), where B = integral breadth of the peak, and the points highlighted in red have been excluded. To calculate crystallite size and strain, the following relationships were used: B = /<D>cosθ + 4εtanθ, where <D> is the average crystallite size, λ is the wavelength, ε is the non-uniform strain (microstrain), and the Scherrer constant K ≈ 1.

Extended Data Figure 5 Electrochemical surface area measurement.

a, b, Determination of double-layer capacitance over a range of scan rates for an OD-Cu 1 electrode after 1 h bulk electrolysis. c, d, Determination of double-layer capacitance over a range of scan rates for an OD-Cu 2 electrode after 12 h bulk electrolysis at –0.3 V versus RHE in 0.1 M KOH. a, c, Cyclic voltammagrams taken over a range of scan rates. b, d, Current due to double-layer charging plotted against cyclic voltammetry scan rate.

Extended Data Figure 6 Representative bulk-electrolysis data for CO reduction on OD-Cu 1.

a, Current density over time for the reduction of Cu2O to form active OD-Cu. b, Current density over time (left) for OD-Cu 1 at –0.4 V versus RHE in 0.1 M KOH, saturated with 1 atm CO and Faraday efficiency over time (right) for H2 (green), C2H4 (red), and C2H6 (blue). Efficiencies for EtOH and AcO were obtained at the end of the electrolysis.

Extended Data Figure 7 Representative NMR spectrum for an OD-Cu 1 bulk electrolysis at –0.5 V versus RHE in 0.1 M KOH, saturated with 2.4 atm CO.

DMSO, dimethyl sulphoxide.

Extended Data Figure 8 Additional Tafel data collected in 0.1 M KOH, saturated with 1 atm CO.

a, Geometric current density for CO reduction versus potential for OD-Cu 2 and Cu nanoparticles. b, Surface-area-normalized current density for H2 evolution versus potential for OD-Cu 1, OD-Cu 2, Cu nanoparticles and polycrystalline Cu foil.

Extended Data Figure 9 CO reduction bulk electrolysis data for OD-Cu 1 in 1 M KOH, saturated with 1 atm CO.

a, Faraday efficiency for various products versus potential. b, Total current density and partial current density for CO reduction versus potential. c, d, SEM images of OD-Cu 1 after electrolysis in 1 M KOH.

Extended Data Table 1 Summary of CO reduction total geometric current densities and Faraday efficiencies for OD-Cu and Cu nanoparticle electrodes
Extended Data Table 2 Capacitance values and surface roughness factors measured using cyclic voltammetry for selected electrodes discussed in this report

PowerPoint slides

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Li, C., Ciston, J. & Kanan, M. Electroreduction of carbon monoxide to liquid fuel on oxide-derived nanocrystalline copper. Nature 508, 504–507 (2014). https://doi.org/10.1038/nature13249

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nature13249

Further reading

Comments

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing