Nanostructured Ir-based electrocatalysts for oxygen evolution prepared by galvanic displacement of Co and Ni

Proton exchange membrane (PEM) electrolysers are promising devices to produce hydrogen as a green fuel. Currently, this technology is limited by the sluggish kinetics of the oxygen evolution reaction (OER). In this work, we describe an environmentally safe method for the preparation of Ir oxide thin...

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Detalles Bibliográficos
Autores: Holde, Freja Bech, Sebastián-Pascual, Paula, Dalby, Kim Nicole, Gómez, Elvira, Escudero-Escribano, María
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2023
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/341354
Acceso en línea:http://hdl.handle.net/10261/341354
https://api.elsevier.com/content/abstract/scopus_id/85169004544
Access Level:acceso abierto
Palabra clave:Deep eutectic solvent
Electrodeposition
Galvanic displacement reaction
Iridium oxide
Oxygen evolution reaction
Descripción
Sumario:Proton exchange membrane (PEM) electrolysers are promising devices to produce hydrogen as a green fuel. Currently, this technology is limited by the sluggish kinetics of the oxygen evolution reaction (OER). In this work, we describe an environmentally safe method for the preparation of Ir oxide thin films (IrO2) for OER. Electrodeposition of Co and Ni was performed in the non-toxic choline chloride:urea deep eutectic solvent (ChCl:urea DES), followed by galvanic displacement reaction (GDR) of Co and Ni by Ir(IV). We evaluated how the GDR conditions, such as the metal replaced (Co or Ni), time and temperature affect both the activity and stability of the deposited IrO2 films on gold substrates. We observed that GDR of Ni at 90 °C induces morphological changes on the IrO2 nanostructures which resulted in higher activity and stability towards OER. We highlight that not only reducing mass loadings of Ir but also tuning the surface morphology and structure controlling the synthesis preparation, as well as investigating the role of the substrate, are key to design more active and stable OER electrocatalysts.