Unveiling the electrochemical behavior of extended interlayer molybdenum disulfide cathode in rechargeable magnesium anode batteries

Considering rechargeable magnesium anode batteries (RMABs), this work presents the thermochemical synthesis of nanostructured MoS 2 -1T (theoretical capacity ≈ 670 mAhg −1 ) and its potential as cathode for RMABs utilizing hybrid electrolyte (Mg 2+ /Li + ) system. The X-ray diffraction, Raman spectroscopy, field emission scanning electron microscopy, high resolution transmission electron microscopy and BET analysis revealed the extended interlayer, nanostructured features and higher surface area of MoS 2 -1T. Electrochemical performance of MoS 2 -1T in the hybrid electrolyte system, outperformed the MoS 2 -2H as a cathode for RMABs. At a current density of 100 mAg −1 , MoS 2 -1T exhibits higher capacity (≈421 mAhg −1 ) as compared to MoS 2 -2H (≈302 mAhg −1 ) with capacity retention of ≈ 57 % and ≈ 40 % over 100 cycles, respectively. The lower value of charge transfer resistance for MoS 2 -1T indicates the improved interfacial charge-transfer kinetics compared to the MoS 2 -2H. The cyclic voltammetry and galvanostatic intermittent titration technique are used to reveal the electrochemical reaction kinetics and diffusion coefficients (10 −8 -10 −10 cm 2 s −1 ). The post-mortem analysis confirms the dual cation insertion and structural integrity during prolonged cycling. These results highlight that combination of strategic phase engineering and use of hybrid electrolyte effectively mitigates the kinetic and interfacial limitations, advancing high-performance cathode development for next-generation RMABs.