@article{34198, author = {Jennifer Ludwig and Dennis Nordlund and Marca M Doeff and Tom Nilges}, title = {Synthesis and characterization of metastable, 20 nm-sized Pna 2 1 -LiCoPO 4 nanospheres}, abstract = {

The majority of research activities on LiCoPO4 are focused on the phospho-olivine (space group Pnma), which is a promising high-voltage cathode material for Li-ion batteries. In contrast, comparably little is known about its metastable Pna21 modification. Herein, we present a comprehensive study on the structure–property relationships of 15–20 nm Pna21-LiCoPO4 nanospheres prepared by a simple microwave-assisted solvothermal process. Unlike previous reports, the results indicate that the compound is non-stoichiometric and shows cation-mixing with Co ions on the Li sites, which provides an explanation for the poor electrochemical performance. Co L2,3-edge X-ray absorption spectroscopic data confirm the local tetrahedral symmetry of Co2+. Comprehensive studies on the thermal stability using thermogravimetric analysis, differential scanning calorimetry, and in situ powder X-ray diffraction show an exothermic phase transition to olivine Pnma-LiCoPO4 at 527 °C. The influence of the atmosphere and the particle size on the thermal stability is also investigated.

}, year = {2017}, journal = {Journal of Solid State Chemistry}, volume = {248}, pages = {9 - 17}, month = {04/2017}, issn = {00224596}, doi = {10.1016/j.jssc.2017.01.015}, language = {eng}, }