The role of alkali metal cations and platinum-surface hydroxyl in the alkaline hydrogen evolution reaction

ABSTRACT 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

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SIMILAR CONTENT BEING VIEWED BY OTHERS UNDERSTANDING HYDROGEN ELECTROCATALYSIS BY PROBING THE HYDROGEN-BOND NETWORK OF WATER AT THE ELECTRIFIED PT–SOLUTION INTERFACE Article 06 July 2023

ACID ANION ELECTROLYTE EFFECTS ON PLATINUM FOR OXYGEN AND HYDROGEN ELECTROCATALYSIS Article Open access 18 February 2022 NON-IRIDIUM-BASED ELECTROCATALYST FOR DURABLE ACIDIC OXYGEN EVOLUTION

REACTION IN PROTON EXCHANGE MEMBRANE WATER ELECTROLYSIS Article 20 October 2022 DATA AVAILABILITY 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

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multifunctional wavefunction analyzer. _J. Comput. Chem._ 33, 580–592 (2012). Article  PubMed  Google Scholar  Download references ACKNOWLEDGEMENTS 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. AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * Department of Chemistry and

Biochemistry, University of California, Los Angeles, CA, USA Aamir Hassan Shah, Zisheng Zhang, Sibo Wang, Guangyan Zhong, Chengzhang Wan, Anastassia N. Alexandrova & Xiangfeng Duan *

Department of Materials Science and Engineering, University of California, Los Angeles, CA, USA Zhihong Huang, Chengzhang Wan & Yu Huang * California NanoSystems Institute, University of

California, Los Angeles, CA, USA Yu Huang & Xiangfeng Duan Authors * Aamir Hassan Shah View author publications You can also search for this author inPubMed Google Scholar * Zisheng

Zhang View author publications You can also search for this author inPubMed Google Scholar * Zhihong Huang View author publications You can also search for this author inPubMed Google

Scholar * Sibo Wang View author publications You can also search for this author inPubMed Google Scholar * Guangyan Zhong View author publications You can also search for this author

inPubMed Google Scholar * Chengzhang Wan View author publications You can also search for this author inPubMed Google Scholar * Anastassia N. Alexandrova View author publications You can

also search for this author inPubMed Google Scholar * Yu Huang View author publications You can also search for this author inPubMed Google Scholar * Xiangfeng Duan View author publications

You can also search for this author inPubMed Google Scholar CONTRIBUTIONS X.D. conceived the research. The experiments were carried out by A.H.S. with assistance from Z.H., S.W., G.Z. and

C.W. under the supervision of Y.H. and X.D. The calculations were carried out by Z.Z. under the supervision of A.N.A. The manuscript was written by A.H.S., Z.Z., A.N.A., Y.H. and X.D.

CORRESPONDING AUTHORS Correspondence to Anastassia N. Alexandrova, Yu Huang or Xiangfeng Duan. ETHICS DECLARATIONS COMPETING INTERESTS The authors declare no competing interests. PEER REVIEW

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Reprints and permissions 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 Download citation * Received: 10 February 2022 * Accepted: 31 August 2022 * Published:

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