The platinum-catalysed hydrogen evolution reaction (HER) generally shows poorer kinetics in alkaline electrolyte and represents a key challenge for alkaline water electrolysis. In the presence of alkali metal cations and hydroxyl anions, the electrode–electrolyte (platinum–water) interface in an alkaline electrolyte is far more complex than that in an acidic electrolyte. Here we combine electrochemical impedance spectroscopy and an electrical transport spectroscopy approach to probe and understand the fundamental role of different cations (Li+, Na+ and K+) in HER kinetics. Our integrated studies suggest that the alkali metal cations play an indirect role in modifying the HER kinetics, with the smaller cations being less destabilizing to the hydroxyl adsorbate (OHad) species in the HER potential window, which favours a higher coverage of OHad on the platinum surface. The surface OHad species are highly polar and act as both electronically favoured proton acceptors and geometrically favoured proton donors to promote water dissociation in alkaline media, thus boosting the Volmer-step kinetics and the HER activity.
This is a preview of subscription content, access via your institution
Access Nature and 54 other Nature Portfolio journals
Get Nature+, our best-value online-access subscription
$29.99 per month
cancel any time
Subscribe to this journal
Receive 12 digital issues and online access to articles
$119.00 per year
only $9.92 per issue
Rent or buy this article
Get just this article for as long as you need it
Prices may be subject to local taxes which are calculated during checkout
The data that support the plots within this paper and other findings of this study are available from the corresponding author upon reasonable request. The DFT-optimized geometries and AIMD trajectories are available in the Zenodo data repository at https://doi.org/10.5281/zenodo.7026971.
Sheng, W., Gasteiger, H. A. & Shao-Horn, Y. Hydrogen oxidation and evolution reaction kinetics on platinum: acid vs alkaline electrolytes. J. Electrochem. Soc. 157, B1529–B1536 (2010).
Li, L., Wang, P., Shao, Q. & Huang, X. Recent progress in advanced electrocatalyst design for acidic oxygen evolution reaction. Adv. Mater. 33, 2004243–2004266 (2021).
Gasteiger, H. A., Panels, J. E. & Yan, S. G. Dependence of PEM fuel cell performance on catalyst loading. J. Power Sources 127, 162–171 (2004).
Nørskov, J. K. et al. Trends in the exchange current for hydrogen evolution. J. Electrochem. Soc. 152, J23–J26 (2005).
Zhang, W. et al. WOx-surface decorated PtNi@Pt dendritic nanowires as efficient pH-universal hydrogen evolution electrocatalysts. Adv. Energy Mater. 11, 2003192–2003198 (2021).
Sheng, W., Myint, M., Chen, J. G. & Yan, Y. Correlating the hydrogen evolution reaction activity in alkaline electrolytes with the hydrogen binding energy on monometallic surfaces. Energy Environ. Sci. 6, 1509–1512 (2013).
Chen, X., McCrum, I. T., Schwarz, K. A., Janik, M. J. & Koper, M. T. M. Co-adsorption of cations as the cause of the apparent pH dependence of hydrogen adsorption on a stepped platinum single-crystal electrode. Angew. Chem. Int. Ed. 56, 15025–15029 (2017).
McCrum, I. T., Chen, X., Schwarz, K. A., Janik, M. J. & Koper, M. T. M. Effect of step density and orientation on the apparent pH dependence of hydrogen and hydroxide adsorption on stepped platinum surfaces. J. Phys. Chem. C. 122, 16756–16764 (2018).
Ledezma-Yanez, I. et al. Interfacial water reorganization as a pH-dependent descriptor of the hydrogen evolution rate on platinum electrodes. Nat. Energy 2, 17031 (2017).
Seto, K., Iannelli, A., Love, B. & Lipkowski, J. The influence of surface crystallography on the rate of hydrogen evolution at Pt electrodes. J. Electroanal. Chem. Interfacial Electrochem. 226, 351–360 (1987).
Markovića, N. M., Sarraf, S. T., Gasteiger, H. A. & Ross, P. N. Hydrogen electrochemistry on platinum low-index single-crystal surfaces in alkaline solution. J. Chem. Soc. Faraday Trans. 92, 3719–3725 (1996).
Marković, N., Grgur, B. & Ross, P. N. Temperature-dependent hydrogen electrochemistry on platinum low-index single-crystal surfaces in acid solutions. J. Phys. Chem. B. 101, 5405–5413 (1997).
Subbaraman, R. et al. Enhancing hydrogen evolution activity in water splitting by tailoring Li+–Ni(OH)2–Pt interfaces. Science 334, 1256–1260 (2011).
Subbaraman, R. et al. Trends in activity for the water electrolyser reactions on 3d M(Ni,Co,Fe,Mn) hydr(oxy)oxide catalysts. Nat. Mater. 11, 550–557 (2012).
Li, J. et al. Experimental proof of the bifunctional mechanism for the hydrogen oxidation in alkaline media. Angew. Chem. Int. Ed. 56, 15594–15598 (2017).
Liu, E. et al. Unifying the hydrogen evolution and oxidation reactions kinetics in base by identifying the catalytic roles of hydroxyl–water–cation adducts. J. Am. Chem. Soc. 141, 3232–3239 (2019).
Cong, Y. et al. Uniform Pd0.33Ir0.67 nanoparticles supported on nitrogen-doped carbon with remarkable activity toward the alkaline hydrogen oxidation reaction. J. Mater. Chem. A 7, 3161–3169 (2019).
Qiu, Y. et al. BCC-phased PdCu alloy as a highly active electrocatalyst for hydrogen oxidation in alkaline electrolytes. J. Am. Chem. Soc. 140, 16580–16588 (2018).
McCrum, I. T. & Koper, M. T. M. The role of adsorbed hydroxide in hydrogen evolution reaction kinetics on modified platinum. Nat. Energy 5, 891–899 (2020).
Xue, S. et al. Influence of alkali metal cations on the hydrogen evolution reaction activity of Pt, Ir, Au, and Ag electrodes in alkaline electrolytes. ChemElectroChem 5, 2326–2329 (2018).
Monteiro, M. C. O., Goyal, A., Moerland, P. & Koper, M. T. M. Understanding cation trends for hydrogen evolution on platinum and gold electrodes in alkaline media. ACS Catal. 11, 14328–14335 (2021).
Weber, D., Janssen, M. & Oezaslan, M. Effect of monovalent cations on the HOR/HER activity for Pt in alkaline environment. J. Electrochem. Soc. 166, F66–F73 (2019).
van der Niet, M. J. T. C., Garcia-Araez, N., Hernández, J., Feliu, J. M. & Koper, M. T. M. Water dissociation on well-defined platinum surfaces: the electrochemical perspective. Catal. Today 202, 105–113 (2013).
Huang, B. et al. Cation- and pH-dependent hydrogen evolution and oxidation reaction kinetics. JACS Au 1, 1674–1687 (2021).
Ding, M. et al. An on-chip electrical transport spectroscopy approach for in situ monitoring electrochemical interfaces. Nat. Commun. 6, 7867 (2015).
Ding, M. et al. On-chip in situ monitoring of competitive interfacial anionic chemisorption as a descriptor for oxygen reduction kinetics. ACS Cent. Sci. 4, 590–599 (2018).
Yoo, H.-W., Cho, S.-Y., Jeon, H.-J. & Jung, H.-T. Well-defined and high resolution Pt nanowire arrays for a high performance hydrogen sensor by a surface scattering phenomenon. Anal. Chem. 87, 1480–1484 (2015).
Kiyohara, K. & Minami, R. Hydration and dehydration of monovalent cations near an electrode surface. J. Chem. Phys. 149, 014705–014714 (2018).
Rebollar, L. et al. ‘Beyond adsorption’ descriptors in hydrogen electrocatalysis. ACS Catal. 10, 14747–14762 (2020).
Mills, J. N., McCrum, I. T. & Janik, M. J. Alkali cation specific adsorption onto fcc(111) transition metal electrodes. Phys. Chem. Chem. Phys. 16, 13699–13707 (2014).
Ringe, S. et al. Understanding cation effects in electrochemical CO2 reduction. Energy Environ. Sci. 12, 3001–3014 (2019).
Mähler, J. & Persson, I. A study of the hydration of the alkali metal Ions in aqueous solution. Inorg. Chem. 51, 425–438 (2012).
McCrum, I. T. & Janik, M. J. First principles simulations of cyclic voltammograms on stepped Pt(553) and Pt(533) electrode surfaces. ChemElectroChem 3, 1609–1617 (2016).
McCrum, I. T. & Janik, M. J. pH and alkali cation effects on the Pt cyclic voltammogram explained using density functional theory. J. Phys. Chem. C. 120, 457–471 (2016).
Lust, E. in Encyclopedia of Electrochemistry (ed. Bard, A. J.) (Wiley, 2007); https://doi.org/10.1002/9783527610426.bard010204
Garlyyev, B., Xue, S., Watzele, S., Scieszka, D. & Bandarenka, A. S. Influence of the nature of the alkali metal cations on the electrical double-layer capacitance of model Pt(111) and Au(111) electrodes. J. Phys. Chem. Lett. 9, 1927–1930 (2018).
Goyal, A. & Koper, M. T. Understanding the role of mass transport in tuning the hydrogen evolution kinetics on gold in alkaline media. J. Chem. Phys. 155, 134705–134715 (2021).
Li, M. et al. Ultrafine jagged platinum nanowires enable ultrahigh mass activity for the oxygen reduction reaction. Science 354, 1414–1419 (2016).
Adamo, C. & Barone, V. Toward reliable density functional methods without adjustable parameters: the PBE0 model. J. Chem. Phys. 110, 6158–6170 (1999).
Kresse, G. & Joubert, D. From ultrasoft pseudopotentials to the projector augmented-wave method. Phys. Rev. B 59, 1758–1775 (1999).
Kresse, G. & Furthmüller, J. Efficiency of ab-initio total energy calculations for metals and semiconductors using a plane-wave basis set. Comput. Mater. Sci. 6, 15–50 (1996).
Kresse, G. & Furthmüller, J. Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set. Phys. Rev. B 54, 11169–11186 (1996).
Kresse, G. & Hafner, J. Ab initio molecular dynamics for liquid metals. Phys. Rev. B. 47, 558–561 (1993).
Kresse, G. & Hafner, J. Ab initio molecular-dynamics simulation of the liquid-metal–amorphous-semiconductor transition in germanium. Phys. Rev. B 49, 14251–14269 (1994).
Grimme, S., Antony, J., Ehrlich, S. & Krieg, H. A consistent and accurate ab initio parametrization of density functional dispersion correction (DFT-D) for the 94 elements H–Pu. J. Chem. Phys. 132, 154104–1541023 (2010).
Yu, M. & Trinkle, D. R. Accurate and efficient algorithm for Bader charge integration. J. Chem. Phys. 134, 064111–064119 (2011).
Steinmann, S. N., Michel, C., Schwiedernoch, R. & Sautet, P. Impacts of electrode potentials and solvents on the electroreduction of CO2: a comparison of theoretical approaches. Phys. Chem. Chem. Phys. 17, 13949–13963 (2015).
Chalk, S. J. The IUPAC Gold Book website (2019); https://doi.org/10.1351/goldbook.S05917
Humphrey, W., Dalke, A. & Schulten, K. VMD: visual molecular dynamics. J. Mol. Graph. 14, 33–38 (1996).
Lu, T. Molclus program, version 188.8.131.52 (Beijing Kein Research Center for Natural Science, 2016).
Becke, A. D. Becke’s three parameter hybrid method using the LYP correlation functional. J. Chem. Phys. 98, 5648–5652 (1993).
Tirado-Rives, J. & Jorgensen, W. L. Performance of B3LYP density functional methods for a large set of organic molecules. J. Chem. Theory Comput. 4, 297–306 (2008).
Schäfer, A., Huber, C. & Ahlrichs, R. Fully optimized contracted Gaussian basis sets of triple zeta valence quality for atoms Li to Kr. J. Chem. Phys. 100, 5829–5835 (1994).
Frisch, M. et al. Gaussian 16, Revision C.01 (Gaussian, Inc., 2016).
Grimme, S., Ehrlich, S. & Goerigk, L. Effect of the damping function in dispersion corrected density functional theory. J. Comput. Chem. 32, 1456–1465 (2011).
Lu, T. & Chen, F. Multiwfn: a multifunctional wavefunction analyzer. J. Comput. Chem. 33, 580–592 (2012).
X.D. acknowledges support from the National Science Foundation award 1800580. Y.H. acknowledges the gracious support by NewHydrogen, Inc. Theoretical research was supported by the DOE-BES DE-SC0019152 grant to A.N.A. An award of computer time was provided by NERSC and the Innovative and Novel Computational Impact on Theory and Experiment (INCITE) program. This research used resources of the Argonne Leadership Computing Facility, which is a DOE Office of Science User Facility supported under Contract DE-AC02-06CH11357.
The authors declare no competing interests.
Peer review information
Nature Catalysis thanks Marcella Iannuzzi and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.
Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
Springer Nature or its licensor holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.
About this article
Cite this article
Shah, A.H., Zhang, Z., Huang, Z. et al. The role of alkali metal cations and platinum-surface hydroxyl in the alkaline hydrogen evolution reaction. Nat Catal 5, 923–933 (2022). https://doi.org/10.1038/s41929-022-00851-x
This article is cited by
Cations in alkaline hydrogen electrocatalysis
Nature Catalysis (2022)