Synthesis, Characterization, and Electrochemical Behavior of LiMn(x)Fe((1−x))PO(4) Composites Obtained from Phenylphosphonate-Based Organic-Inorganic Hybrids

The synthesis of organic-inorganic hybrid compounds based on phenylphosphonate and their use as precursors to form LiMn(x)Fe((1−x))PO(4) composites containing carbonaceous substances with sub-micrometric morphology are presented. The experimental procedure includes the preliminary synthesis of Fe(2+) and/or Mn(2+) phenylphosphonates with the general formula Fe((1−x))Mn(x)[(C(6)H(5)PO(3))(H(2)O)] (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 LiMn(x)Fe((1−x))PO(4) particles. After a structural and morphological characterization, the electrochemical behavior of lithium iron manganese phosphates has been compared to the one of pristine LiFePO(4) and LiMnPO(4), in order to evaluate the doping influence on the material.