Size-controlled chevrel Mo₆S₈ as cathode material for Mg rechargeable battery

Nanoscale Chevrel Mo₆S₈ powders are synthesized by molten salt synthesis. Synthesized Mo₆S₈ powders have different mean particle sizes which are dependent on a ratio of salt to precursor. The particle sizes of Mo₆S₈ powders changes along with the ratio increase. Mo₆S₈ (6:1) demonstrates the best electrochemical characteristics among the synthesized Mo ₆S₈ powders although the Mo₆S₈ (4:1) has the smallest particle size. Mo₆S₈ (6:1) shows a reversible capacity of 83.9 mAhg-1, which is 27.5% and 33% improved value over Mo₆S₈ (2:1) and Mo₆S₈ (4:1) at a current density of 0.2C, respectively. The superior electrochemical properties of Mo₆S₈ (6:1) are attributed to the balanced particle size which provides proper contact area with electrolyte and the shortened Mg²⁺ diffusion length. The Mo₆S₈ (4:1) has the smallest particle size but further reduction of particle size from Mo ₆S₈ (6:1) is not advantageous.