, Volume 9, Issue 4, pp 526–530 | Cite as

Surface Reconstruction of Polycrystalline Cu Electrodes in Aqueous KHCO3 Electrolyte at Potentials in the Early Stages of CO2 Reduction

  • Youn-Geun Kim
  • Jack H. Baricuatro
  • Manuel P. SoriagaEmail author
Original Research


The reconstruction of the Cu(pc) polycrystalline surface at potentials that correspond to the early stages of CO2 reduction in 0.1 M KHCO3 was investigated by electrochemical scanning tunneling microscopy (ECSTM) at −0.90 V (SHE). A kinetically hindered surface reconstruction of the topmost layers of Cu(pc) into the (100) face was observed, reminiscent of the transformation previously reported at the same electrode potential in 0.1 M KOH. Evidently, the same reconstructed surface, Cu(pc)-[Cu(100)], can be generated in either 0.1 M KHCO3 (pH 8) or 0.1 M KOH (pH 13). In addition, only minimal structural disruption was observed when the reconstructed surface was transferred from KHCO3 to KOH electrolyte, and vice versa, provided the solution exchange was executed potentiostatically at −0.90 V. The structural convergence toward the same (100) facet regardless of pH or supporting electrolyte strongly suggests that the Cu(pc) → Cu(pc)-[Cu(100)] surface reorganization is a general phenomenon driven primarily by the rather negative potential applied on the electrode.

Graphical abstract


Surface reconstruction of Cu(pc) under CO2-reduction potentials Operando electrochemical scanning tunneling microscopy Electrochemical CO2 reduction Cu(pc) to Cu(pc)-[Cu(100)] surface reconstruction 



This material is based upon the work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the US Department of Energy under Award No. DE-SC0004993.


  1. 1.
    Y. Hori, in Modern Aspects of Electrochemistry, ed. by C. G. Vayenas, R. E. White, M. E. Gamboa-Aldeco. Electrochemical CO2 Reduction on Metal Electrodes (Springer, New York, 2008), p. 89CrossRefGoogle Scholar
  2. 2.
    M. Gattrell, N. Gupta, A. Co, A review of the aqueous electrochemical reduction of CO2 to hydrocarbons at copper. J. Electroanal. Chem. 594(1), 1–19 (2006)CrossRefGoogle Scholar
  3. 3.
    K.P. Kuhl, E.R. Cave, D.N. Abram, T.F. Jaramillo, New insights into the electrochemical reduction of carbon dioxide on metallic copper surfaces. Energy Environ. Sci. 5(5), 7050 (2012)CrossRefGoogle Scholar
  4. 4.
    B. Kumar, M. Llorente, J. Froehlich, T. Dang, A. Sathrum, C.P. Kubiak, Photochemical and photoelectrochemical reduction of CO2. Annu. Rev. Phys. Chem. 63(1), 541–569 (2012)CrossRefPubMedGoogle Scholar
  5. 5.
    C. Shi, K. Chan, J.S. Yoo, J.K. Nørskov, Barriers of electrochemical CO2 reduction on transition metals. Org. Process. Res. Dev. 20(8), 1424–1430 (2016)CrossRefGoogle Scholar
  6. 6.
    J.H. Montoya, A.A. Peterson, J.K. Nørskov, Insights into C-C coupling in CO2 electroreduction on copper electrodes. ChemCatChem 5(3), 737–742 (2013)CrossRefGoogle Scholar
  7. 7.
    A.J. Garza, A.T. Bell, M. Head-Gordon, Mechanism of CO2 reduction at copper surfaces: pathways to C2 products. ACS Catal. 8(2), 1490–1499 (2018)CrossRefGoogle Scholar
  8. 8.
    M.P. Soriaga, J.H. Baricuatro, A.C. Javier, Y.-G. Kim, K.D. Cummins, C.F. Tsang, J.C. Hemminger, N.N. Bui, J.L. Stickney, in Encyclopedia of Interfacial Chemistry: Surface Science and Electrochemistry, ed. by K. Wandelt. Electrochemical Surface Science of CO2 Reduction at Well-Defined Cu Electrodes: Surface Characterization by Emersion, Ex Situ, In Situ, and Operando Methods (Elsevier Inc., Oxford, 2017), p. 1Google Scholar
  9. 9.
    Y.-G. Kim, A. Javier, J.H. Baricuatro, M.P. Soriaga, Seriatim ECSTM-DEMS of Cu-catalyzed reduction of CO in alkaline solution: Operando correlation of electrode-surface atomic structure with product selectivity. Curr. Top. Catal. 13, 1 (2017)CrossRefGoogle Scholar
  10. 10.
    Y. Hori, I. Takahashi, O. Koga, N. Hoshi, Selective formation of C2 compounds from electrochemical reduction of CO2 at a series of copper single crystal electrodes. J. Phys. Chem. B 106(1), 15–17 (2002)CrossRefGoogle Scholar
  11. 11.
    K.J.P. Schouten, Z. Qin, E.P. Gallent, M.T.M. Koper, Two pathways for the formation of ethylene in CO reduction on single-crystal copper electrodes. J. Am. Chem. Soc. 134(24), 9864–9867 (2012)CrossRefPubMedGoogle Scholar
  12. 12.
    Y.-G. Kim, A. Javier, J.H. Baricuatro, D. Torelli, K.D. Cummins, C.F. Tsang, J.C. Hemminger, M.P. Soriaga, Surface reconstruction of pure-Cu single-crystal electrodes under CO-reduction potentials in alkaline solutions: a study by seriatim ECSTM-DEMS. J. Electroanal. Chem. 780, 290–295 (2016)CrossRefGoogle Scholar
  13. 13.
    Y.-G. Kim, J.H. Baricuatro, A. Javier, J.M. Gregoire, M.P. Soriaga, The evolution of the polycrystalline copper surface, first to Cu(111) and then to Cu(100), at a fixed CO2RR potential: a study by operando EC-STM. Langmuir 30, 15053 (2014)CrossRefPubMedGoogle Scholar
  14. 14.
    Y.-G. Kim, A. Javier, J.H. Baricuatro, M.P. Soriaga, Regulating the product distribution of co reduction by the atomic-level structural modification of the Cu electrode surface. Electrocatalysis 7, 1 (2016)CrossRefGoogle Scholar
  15. 15.
    Y.-G. Kim, M.P. Soriaga, Cathodic regeneration of a clean and ordered Cu(100)-(1×1) surface from an air-oxidized and disordered electrode: an operando STM study. J. Electroanal. Chem. 734, 7–9 (2014)CrossRefGoogle Scholar
  16. 16.
    Y. Huang, A.D. Handoko, P. Hirunsit, B.S. Yeo, Electrochemical reduction of CO2 using copper single-crystal surfaces: effects of CO* coverage on the selective formation of ethylene. ACS Catal. 7(3), 1749–1756 (2017)CrossRefGoogle Scholar
  17. 17.
    M.R. Singh, Y. Kwon, Y. Lum, J.W. Ager, A.T. Bell, Hydrolysis of electrolyte cations enhances the electrochemical reduction of CO2 over Ag and Cu. J. Am. Chem. Soc. 138, 13006 (2016)CrossRefPubMedGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  • Youn-Geun Kim
    • 1
    • 2
  • Jack H. Baricuatro
    • 1
    • 2
  • Manuel P. Soriaga
    • 1
    • 3
    Email author
  1. 1.Joint Center for Artificial PhotosynthesisCalifornia Institute of TechnologyPasadenaUSA
  2. 2.Division of Chemistry and Chemical EngineeringCalifornia Institute of TechnologyPasadenaUSA
  3. 3.Division of Engineering and Applied ScienceCalifornia Institute of TechnologyPasadenaUSA

Personalised recommendations