Prussian blue analogues for potassium-ion batteries: insights into the electrochemical mechanisms
Journal article, 2023
A comprehensive description of the electrochemical mechanisms of the Prussian Blue Analogue (PBA) K1.67Mn0.65Fe0.35[Fe(CN)6]0.92·0.45H2O is obtained by combining several complementary ex situ and operando physico-chemical characterisation techniques. This particular PBA, which shows very good electrochemical performance as a cathode material in potassium-ion batteries (PIBs), undergoes three successive redox reactions during the (de-)potassiation that are hereby identified by ex situ57Fe Mössbauer spectroscopy and operando Mn and Fe K-edge X-ray absorption spectroscopy. These reactions come along with notable modifications of the crystal structure, which are followed in real time by operando X-ray diffraction. The correlation of these results, interpreted with the support of chemometric methods, also reveals the limitations of this PBA, probably related to the deactivation of the Mn undergoing extensive reversible Jahn-Teller distortion during cycling as well as possible dissolution in the electrolyte. These results underline that optimisation of the chemical composition of PBAs is a crucial step towards the preparation of reliable and stable PBA-based cathodes for PIBs.
Author
Phuong Nam Le Pham
Institut Charles Gerhardt Montpellier
Centre national de la recherche scientifique (CNRS)
Romain Wernert
University of Bordeaux
Centre national de la recherche scientifique (CNRS)
Institut Charles Gerhardt Montpellier
Maëlle Cahu
Institut Charles Gerhardt Montpellier
Moulay Tahar Sougrati
Centre national de la recherche scientifique (CNRS)
Institut Charles Gerhardt Montpellier
Giuliana Aquilanti
Elettra Sincrotrone Trieste
Patrik Johansson
Centre national de la recherche scientifique (CNRS)
Chalmers, Physics, Materials Physics
L. Monconduit
Centre national de la recherche scientifique (CNRS)
Institut Charles Gerhardt Montpellier
L. Stievano
Centre national de la recherche scientifique (CNRS)
Institut Charles Gerhardt Montpellier
Journal of Materials Chemistry A
20507488 (ISSN) 20507496 (eISSN)
Vol. 11 6 3091-3104Subject Categories
Inorganic Chemistry
Materials Chemistry
Other Chemical Engineering
DOI
10.1039/d2ta08439b