Characterization of soft-combustion-derived NASICON-type Li2Co2(MoO4)3 for lithium batteries

This work describes the synthesis of a new polyanion material, Li2Co2(MoO4)3, belonging to the NASICON family. A low-temperature soft-combustion method using glycine as a soft-combustion fuel was adopted to obtain single-phase powders of the new material at a temperature as low as 300 °C. Li2Co2(MoO4)3 was found to crystallize in an orthorhombic structure (space group Pmmm) with lattice parameters a = 17.584(7) Å, b = 10.464(4) Å and c = 5.102(9) Å. The electronic state of each element present in the new material was confirmed by X-ray photoelectron spectroscopic analysis. The powders were analyzed using inductively coupled plasma emission spectroscopy. The microstructural analysis revealed that the particles (5–10 μm) have a rather columnar shape. The electrochemistry redox behavior of the new material was studied, for the first time, and the material as positive electrode was found to exhibit topotactic Li+ extraction/insertion in lithium-containing test cells.