visitante ::
identificación
|
|||||||||||||||
Buscar | Enviar | Ayuda | Servicio de Bibliotecas | Sobre el DDD | Català English Español |
Página principal > Artículos > Artículos publicados > Unveiling the role of counter-anions in amorphous transition metal-based oxygen evolution electrocatalysts |
Fecha: | 2023 |
Resumen: | At the initial stage of the oxygen evolution reaction (OER) most electrocatalysts undergo structural and chemical surface reconstruction. While this reconstruction strongly influences their performance, it is frequently overlooked. Herein, we analyze the role of the oxidized anions, which is particularly neglected in most previous works. We introduce a range of different anionic groups (Cl, CHCOO, NO , SO ) on the surface of an amorphous ZnCoNiO catalyst by a facile proton etching and ion exchange method from a ZIF-8 self-sacrificial template. The structural and chemical properties of the obtained set of materials are thoroughly analysed and correlated with their electrocatalytic performance to study the effect of surface anionic groups, phase transition, metal leaching and defect generation on OER activity. Exploiting the control possibilities provided by the synthesis method here described and employing the uncovered property-performance correlations, the electrocatalyst is optimized. As a result, we produce ZnCoNiO-SO catalysts with outstanding OER performances, including a low overpotential of 252 mV at 10 mA cm with a small Tafel slope of 41. 6 mV dec. Furthermore, this catalyst exhibits remarkable stability with negligible overpotential variation for 100 h. The excellent catalytic properties are rationalized using density functional theory calculations, showing that the surface-adsorbed anions, particularly SO , can stabilize the OOH* intermediate, thus enhancing the OER activity. This work offers new insight into the roles of metal leaching and surface-adsorbed anions in the OER progress and facilitates the rational design of highly-efficient electrocatalysts for OER. |
Ayudas: | Ministerio de Ciencia e Innovación PID2021-124572OB-C31 Ministerio de Ciencia e Innovación PID2020-116093RB-C43 Ministerio de Ciencia e Innovación PID2019-105490RB-C32 Ministerio de Ciencia e Innovación ENE2016-77798-C4-3-R Ministerio de Economía y Competitividad SEV-2017-0706 Ministerio de Economía y Competitividad SEV-2013-0295-17-1 Agència de Gestió d'Ajuts Universitaris i de Recerca 2017/SGR-1246 Agència de Gestió d'Ajuts Universitaris i de Recerca 2017/SGR-327 Agència de Gestió d'Ajuts Universitaris i de Recerca 2017/SGR-128 |
Derechos: | Aquest document està subjecte a una llicència d'ús Creative Commons. Es permet la reproducció total o parcial, la distribució, i la comunicació pública de l'obra, sempre que no sigui amb finalitats comercials, i sempre que es reconegui l'autoria de l'obra original. No es permet la creació d'obres derivades. |
Lengua: | Anglès |
Documento: | Article ; recerca ; Versió sotmesa a revisió |
Materia: | Amorphous oxide ; Anion adsorption ; Structural reconstruction ; Leaching ; Oxygen evolution reaction |
Publicado en: | Applied catalysis. B, Environmental, Vol. 320 (Jan. 2023) , art. 121988, ISSN 0926-3373 |
Preprint 25 p, 3.5 MB |