Volume 10 Issue 1
Synthesis, Characterization, and Electrochemical Behavior of LiMnxFe(1−x)PO4 Composites Obtained from Phenylphosphonate-Based Organic-Inorganic Hybrids
Alessandro Dell’Era, Mauro Pasquali, Elvira Maria Bauer, Stefano Vecchio Ciprioti, Francesca A. Scaramuzzo and Carla Lupi
1Department of Basic and Applied Sciences for Engineering (SBAI), Sapienza University of Rome, Via del Castro Laurenziano 7, 00161 Rome, Italy
2Istituto di Struttura della Materia ISM—CNR, Via Salaria, km. 29.300, C.P. 10, 00015 Rome, Italy
3Department Chemical Engineering Materials Environment DICMA, University Sapienza Rome, Via Eudossiana 18, 00184 Rome, Italy
*Authors to whom correspondence should be addressed.
Abstract
The synthesis of organic-inorganic hybrid compounds based on phenylphosphonate and their use as precursors to form LiMnxFe(1−x)PO4 composites containing carbonaceous substances with sub-micrometric morphology are presented. The experimental procedure includes the preliminary synthesis of Fe2+ and/or Mn2+ phenylphosphonates with the general formula Fe(1−x)Mnx[(C6H5PO3)(H2O)] (with 0 < x < 1), which are then mixed at different molar ratios with lithium carbonate. In this way the carbon, obtained from in situ partial oxidation of the precursor organic part, coats the LiMnxFe(1−x)PO4 particles. After a structural and morphological characterization, the electrochemical behavior of lithium iron manganese phosphates has been compared to the one of pristine LiFePO4 and LiMnPO4, in order to evaluate the doping influence on the material.
Keywords:lithium-ion battery; LiMnxFe(1−x)PO4; carbon coating; pseudo-diffusion coefficient; potential step voltammetry; electrochemical impedance spectroscopy