Octylamine?Supporting Interlayer Expanded Molybdenum Diselenide as a High?Power Cathode for Rechargeable Mg Batteries

Rechargeable Mg batteries (RMBs) are a promising large-scale energy-storage technology with low cost and high safety, but the performance is limited by inferior kinetics of Mg-intercalation cathodes. In present study, an octylamine-supporting interlayer expanded molybdenum diselenide (e-MoSe2) synthesized used as cathode for RMBs, in comparison ordinary crystalline MoSe2. The octylamine molecules introduced show strong interaction MoSe2 layers increase layer spacing significantly from 6.46 to 11.5 Å. e-MoSe2 shows Mg-storage capacity 238 mAh g?1 at 50 mA superior rate 39 10 A g?1, far advantageous over also considerably structure stability during repeated magnesiation/demagnesiation, providing outstanding cycling 1000 cycles. Further electrochemical tests demonstrate Mg2+ diffusion coefficients e-MoSe2. Theoretical computation indicates expansion changes paths “hollow site ? hollow site” Se atom site”, largely decreasing energy barrier improving kinetics. work highlights efficient strategy improvement RMB