<i>Operando</i> Raman and <i>ex situ</i> characterization of an iron-based conductive MOF as a negative electrode in Li-ion batteries

Ciria-Ramos, Isabel (Universidad de Zaragoza) ; Neale, Alex R. ; Hardwick, Laurence J. ; Juarez-Perez, Emilio J. ; Gascón, Ignacio (Universidad de Zaragoza) ; Haro, Marta (Universidad de Zaragoza)

Resumen: An iron-based electrically conductive metal–organic framework (MOF), Fe-HHTP, formed by the coordination of Fe cations and the organic ligand HHTP (2,3,6,7,10,11-hexahydroxytriphenylene), has been synthesized, characterized, and explored as a potential negative electrode for lithium-ion batteries (LIBs). Galvanostatic cycling experiments, with a lower cut-off voltage of 0.1 V vs. Li/Li+, reveal that Fe-HHTP undergoes a significant activation process, resulting in an increase in specific capacity up to 1142 mAh g−1 after ∼220 cycles at a current of 355 mA g−1. Operando Raman spectroscopy during the first lithiation, complemented by ex situ techniques at different cycling stages, demonstrates that both the organic ligands and metal centers actively contribute to Li+ storage. Initially, lithiation occurs primarily at the MOF boundaries, while continuous cycling induces a structural transformation that allows greater accessibility to the inner regions of Fe-HHTP. These results provide a better understanding of the electrochemical and structural behavior of pristine MOFs that allow tailoring their properties for direct application in energy storage devices without the need for high-temperature processes.

Idioma: Inglés

DOI: 10.1039/d5dt00893j

Año: 2025

Publicado en: Dalton Transactions (2025), [12 pp.]
ISSN: 1477-9226

Financiación: info:eu-repo/grantAgreement/ES/DGA/E31-23R
Financiación: info:eu-repo/grantAgreement/ES/MCIU/CNS2023-14197
Financiación: info:eu-repo/grantAgreement/ES/MCIU/CPP2022-009766
Financiación: info:eu-repo/grantAgreement/ES/MCIU/PID2022-140516OB-I00
Financiación: info:eu-repo/grantAgreement/ES/MICIU/CEX2023-001286-S

Tipo y forma: Artículo (Versión definitiva)

Área (Departamento): Área Química Física (Dpto. Química Física)