Incorporation of Fe3+ into MnO2 birnessite for enhanced energy storage: Impact on the structure and the charge storage mechanisms
OLCHOWKA, Jacob
Institut de Chimie de la Matière Condensée de Bordeaux [ICMCB]
Réseau sur le stockage électrochimique de l'énergie [RS2E]
Advanced Lithium Energy Storage Systems - ALISTORE-ERI [ALISTORE-ERI]
Institut de Chimie de la Matière Condensée de Bordeaux [ICMCB]
Réseau sur le stockage électrochimique de l'énergie [RS2E]
Advanced Lithium Energy Storage Systems - ALISTORE-ERI [ALISTORE-ERI]
GUERLOU-DEMOURGUES, Liliane
Institut de Chimie de la Matière Condensée de Bordeaux [ICMCB]
Réseau sur le stockage électrochimique de l'énergie [RS2E]
Advanced Lithium Energy Storage Systems - ALISTORE-ERI [ALISTORE-ERI]
< Reduce
Institut de Chimie de la Matière Condensée de Bordeaux [ICMCB]
Réseau sur le stockage électrochimique de l'énergie [RS2E]
Advanced Lithium Energy Storage Systems - ALISTORE-ERI [ALISTORE-ERI]
Language
en
Article de revue
This item was published in
Journal of Materials Chemistry A. 2024, vol. 12, n° 6, p. 3373-3385
Royal Society of Chemistry
English Abstract
Birnessite δ-MnO2, with its low cost, high theoretical capacity, and stable cycling performance in aqueous electrolytes, holds promise as an electrode material for high-power and cost-effective electrochemical energy storage ...Read more >
Birnessite δ-MnO2, with its low cost, high theoretical capacity, and stable cycling performance in aqueous electrolytes, holds promise as an electrode material for high-power and cost-effective electrochemical energy storage devices. To address its poor electronic conductivity, we incorporated environmentally friendly iron into birnessite and conducted a comprehensive study on its influence on crystal structure, electrochemical reaction mechanisms, and energy storage performance. In this study, a series of birnessite samples with varying iron content (δ-Mn1-xFexO2 with 0 ≤ x ≤ 0.20) were synthesized using solid-state reactions, resulting in well-crystallized particles with micrometric platelet morphology. Through X-ray absorption and Mössbauer spectroscopies, we clearly demonstrated that Fe replaces Mn in the metal oxide layer, while X-ray diffraction revealed that iron content significantly affects interlayer site symmetry and the resulting polytype. The sample with the lowest iron content (δ-Mn0.96Fe0.04O2) exhibits a monoclinic birnessite structure with an O-type interlayer site, while increasing iron content leads to hexagonal symmetry with P-type interlayer sites. Electrochemical investigations indicated that these P-type sites facilitate the diffusion of partially hydrated alkaline ions and exhibit superior rate capabilities compared to the O-type phase. Furthermore, operando XAS revealed that Fe is electrochemically inactive and that the charge storage in birnessite-type phases in a 0.5M K2SO4 electrolyte primarily relies on the redox reaction of Mn. Finally, we determined that P-type δ-Mn0.87Fe0.13O2 achieved the best compromise between enhancing electrical conductivity and maintaining a maximum content of electrochemically active Mn cations.Read less <
ANR Project
Laboratory of excellency for electrochemical energy storage - ANR-10-LABX-0076
Spectromètre EXAFS Rapide pour Cinétiques Chimiques - ANR-10-EQPX-0045
Spectromètre EXAFS Rapide pour Cinétiques Chimiques - ANR-10-EQPX-0045
Origin
Hal imported