A Convenient Approach to Mo₆S₈Chevrel Phase Cathode for Rechargeable Magnesium Battery

A two-step solution chemistry route was used to synthesize ternary Chevrel phase (Cu 2 Mo 6 S 8 ) with 5 h annealing at 1000°C under reducing atmosphere. The approach marks a synthesis route different from hitherto described conventional solid-state methods. X-ray diffraction and scanning electron micrograph shows the formation of ∼1–1.5 μm size cuboidal shape Cu 2 Mo 6 S 8 crystals with unit cell dimensions a ∼ 0.96245 nm and c ∼ 1.01987 nm of molar volume ∼818.14 × 10 −3 nm 3 . De-cuprated Mo 6 S 8 exhibits a discharge capacity ∼76 mAhg −1 with good capacity retention up to ∼50 cycles when cycled at the current rate of 20 mA/g (∼C/6). The excellent rate capability and high Coulombic efficiency (∼99.3% at ∼1.5C rate) of the Mo 6 S 8 cathode renders the solution chemistry route an alternative approach for the synthesis of cuprated Chevrel phase: a known cathode system for magnesium battery.