Abstract
We have synthesized NaCoPO4 and LiCoPO4 via microwave-assisted solvothermal synthesis. The local atomic structure around Co atoms was characterized by means of Co K-edge XANES spectroscopy. Using X-ray diffraction, we have identified two NaCoPO4 phases with Pnma and P6(5) space groups (lattice parameters a = 10.26 angstrom, b = 5.93 angstrom, c = 4.74 angstrom, and a = 10.16 angstrom,b = 10.16 angstrom,c = 23.87 angstrom, respectively) and one LiCoPO4 phase has Pnma space group with lattice parameters a = 10.22 angstrom, b = 5.93 angstrom and c = 4.71 angstrom. Within GGA + U approximation we have calculated the variation of the cell voltage versus Li foil and atomic Bader charges for a wide range of alkali metal concentration in the material. Considering the low cost of the material and high intercalation voltage the synthesized sodium-based material is a good candidate for novel cathode materials.