Highly durable nanoporous Cu2-xS films for efficient hydrogen evolution electrocatalysis under mild pH conditions

Copper-based hydrogen evolution electrocatalysts are promising materials to scale-up hydrogen production due to their reported high current densities; however, electrode durability remains a challenge. Here, we report a facile, cost-effective, and scalable synthetic route to produce Cu2-xS electroca...

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Detalles Bibliográficos
Autores: Fernández-Climent, Roser, Redondo, Jesús, García-Tecedor, Miguel, Spadaro, Maria Chiara, Li, Junnan, Chartrand, Daniel, Schiller, Frederik, Pazos, Jhon, Hurtado, Mikel F., Peña O'Shea, Victor de la, Kornienko, Nikolay, Arbiol, Jordi, Barja, Sara, Mesa, Camilo A., Giménez, Sixto
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:10261/342429
Acceso en línea:http://hdl.handle.net/10261/342429
Access Level:acceso abierto
Palabra clave:Green hydrogen
Mechanistic analysis
Hydrogen evolution reaction
Operando ECSA increase
Electrocatalysis
Cu-based electrodes
Descripción
Sumario:Copper-based hydrogen evolution electrocatalysts are promising materials to scale-up hydrogen production due to their reported high current densities; however, electrode durability remains a challenge. Here, we report a facile, cost-effective, and scalable synthetic route to produce Cu2-xS electrocatalysts, exhibiting hydrogen evolution rates that increase for ∼1 month of operation. Our Cu2-xS electrodes reach a state-of-the-art performance of ∼400 mA cm-2 at -1 V vs RHE under mild conditions (pH 8.6), with almost 100% Faradaic efficiency for hydrogen evolution. The rise in current density was found to scale with the electrode electrochemically active surface area. The increased performance of our Cu2-xS electrodes correlates with a decrease in the Tafel slope, while analyses by X-ray photoemission spectroscopy, operando X-ray diffraction, and in situ spectroelectrochemistry cooperatively revealed the Cu-centered nature of the catalytically active species. These results allowed us to increase fundamental understanding of heterogeneous electrocatalyst transformation and consequent structure-activity relationship. This facile synthesis of highly durable and efficient Cu2-xS electrocatalysts enables the development of competitive electrodes for hydrogen evolution under mild pH conditions.