Interlayer Engineering of VS₂ Nanosheets via In Situ Aniline Intercalative Polymerization toward Long-Cycling...

Rechargeable magnesium batteries (RMBs) show great potential in large-scale energy storage systems, due to Mg²⁺ with high polarity leading to strong interactions within the cathode lattice, and the limited discovery of functional cathode materials with rapid kinetics of Mg²⁺ diffusion and desirable cyclability retards their development. Herein, we innovatively report the confined synthesis of VS₂/polyaniline (VS₂/PANI) hybrid nanosheets. The VS₂/PANI hybrids with expanded interlayer spacing are successfully prepared through the exfoliation of VS₂ and in situ polymerization between VS₂ nanosheets and aniline. The intercalated PANI increases the interlayer spacing of VS₂ from 0.57 to 0.95 nm and improves its electronic conductivity, leading to rapid Mg-ion diffusivity of 10^-10-10^-12 cm² s^-1. Besides, the PANI sandwiched between layers of VS₂ is conducive to maintaining the structural integrity of electrode materials. Benefiting from the above advantages, the VS₂/PANI-1 hybrids present remarkable performance for Mg²⁺ storage, showing high reversible discharge capacity (245 mA h g^-1 at 100 mA g^-1) and impressive long lifespan (91 mA h g^-1 after 2000 cycles at 500 mA g^-1). This work provides new perspectives for designing high-performance cathode materials based on layered materials for RMBs.