title: Making the hydrogen evolution reaction in polymer electrolyte membrane electrolysers even faster.
abstract: Although the hydrogen evolution reaction (HER) is one of the fastest electrocatalytic reactions, modern polymer electrolyte membrane (PEM) electrolysers require larger platinum loadings (∼0.5-1.0 mg cm(-2)) than those in PEM fuel cell anodes and cathodes altogether (∼0.5 mg cm(-2)). Thus, catalyst optimization would help in substantially reducing the costs for hydrogen production using this technology. Here we show that the activity of platinum(111) electrodes towards HER is significantly enhanced with just monolayer amounts of copper. Positioning copper atoms into the subsurface layer of platinum weakens the surface binding of adsorbed H-intermediates and provides a twofold activity increase, surpassing the highest specific HER activities reported for acidic media under similar conditions, to the best of our knowledge. These improvements are rationalized using a simple model based on structure-sensitive hydrogen adsorption at platinum and copper-modified platinum surfaces. This model also solves a long-lasting puzzle in electrocatalysis, namely why polycrystalline platinum electrodes are more active than platinum(111) for the HER.
authors.affiliation: Center for Electrochemical Sciences-CES, Ruhr-Universität Bochum, Universitätsstrasse 150, D-44780 Bochum, Germany.|Analytische Chemie-Elektroanalytik &Sensorik, Ruhr-Universität Bochum, Universitätsstrasse 150, D-44780 Bochum, Germany.
authors.forename: Jakub
authors.initials: J
authors.lastname: Tymoczko
authors.affiliation: Leiden Institute of Chemistry, Leiden University, PO-Box 9502, 2300 RA Leiden, The Netherlands.
authors.forename: Federico
authors.initials: F
authors.lastname: Calle-Vallejo
authors.affiliation: Center for Electrochemical Sciences-CES, Ruhr-Universität Bochum, Universitätsstrasse 150, D-44780 Bochum, Germany.|Analytische Chemie-Elektroanalytik &Sensorik, Ruhr-Universität Bochum, Universitätsstrasse 150, D-44780 Bochum, Germany.
authors.forename: Wolfgang
authors.identifier: http://orcid.org/0000-0003-2916-5223
authors.initials: W
authors.lastname: Schuhmann
authors.affiliation: Center for Electrochemical Sciences-CES, Ruhr-Universität Bochum, Universitätsstrasse 150, D-44780 Bochum, Germany.|Physik-Department ECS, Technische Universität München, James-Franck-Strasse 1, 85748 Garching, Germany.|Nanosystems Initiative Munich (NIM), Schellingstrassee 4, 80799 Munich, Germany.
authors.forename: Aliaksandr S
authors.initials: AS
authors.lastname: Bandarenka
mesh_terms: D002384:Catalysis; D003300:Copper / Q000737:chemistry*; D004563:Electrochemistry; D004566:Electrodes; D004572:Electrolysis; D004573:Electrolytes / Q000737:chemistry*; D006859:Hydrogen / Q000737:chemistry*; D008567:Membranes, Artificial; D010984:Platinum / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D004573:Electrolytes; D008567:Membranes, Artificial; D010984:Platinum; D003300:Copper; D006859:Hydrogen