Materials Chemistry and Physics, Vol.121, No.1-2, 370-377, 2010
Nano-crystalline LiMnPO4 prepared by a new phosphate-formate precursor method
The preparation of homogeneous phosphate-formate precursors by freeze-drying of solutions containing lithium, Mn(II), phosphate and formate ions ensures production of stoichiometric, well crystallized, defectless and nano-sized LiMnPO4 powders at temperatures above 400 degrees C. A systematic study of the influence of the synthesis conditions on the structure and morphology of LiMnPO4 is performed. It is established that the concentration of the solutions subjected to freeze-drying and the annealing temperature strongly affect the structure, particle dimensions and morphology of LiMnPO4. LiMnPO4 with low extent of Li-to-Mn disorder (below 1%) are formed between 500 and 600 degrees C. Uniform and regular particles with close sizes distribution in the 60-120 nin range are prepared from diluted freeze-dried solutions and at relatively low annealing temperature. (C) 2010 Elsevier B.V. All rights reserved.
Keywords:Lithium manganese phosphate;Chemical synthesis;X-ray diffraction;Scanning electron microscopy;FTIR