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Updated: Nov 20, 2025

Author Spotlight: Magnetometric Characterization of Intermediates in the Solid-State Electrochemistry of Redox-Active Metal-Organic Frameworks
Published on: June 9, 2023
Testing the reversible insertion of magnesium in a cation-deficient manganese oxy-spinel through a concentration cell
Alejandro Medina1, Ana I Rodríguez, Carlos Pérez-Vicente
1Departamento de Química Inorgánica e Ingeniería Química, Instituto Universitario de Investigación en Química Fina y Nanoquímica (IUNAN), Universidad de Córdoba, Campus de Rabanales, Edificio Marie Curie, E-14071 Córdoba, Spain. ralcantara@uco.es.
Abstract:
Magnesium-ion batteries could be competitive with lithium-ion batteries, but the reversible intercalation of magnesium in the framework of the host material needs to be verified. A concentration cell was built by using electrodes with different concentrations of magnesium ions in the cubic spinel MgxMn2O4. For this purpose, firstly cations were partially extracted from MgMn2O4 by acid-treatment. This concentration cell was used to test the reversible intercalation of magnesium and the effect of the cationic vacancies. The theoretical results of the percolation energy can explain the lower polarization experimentally observed in the voltage curve of the acid-treated sample. The reversible capacity (ca. 115 mA h g-1) is preserved after charge-discharge cycling.
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