Single-Layered MoS₂ Fabricated by Charge-Driven Interlayer Expansion for Superior...

Single-layered MoS₂ is a promising anode material for lithium-ion batteries (LIBs), sodium-ion batteries (SIBs), and potassium-ion batteries (PIBs) due to its high capacity and isotropic ion transport paths. However, the low intrinsic conductivity and easy-agglomerated feature hamper its applications. Here, a charge-driven interlayer expansion strategy that Co²⁺ replaces Mo⁴⁺ in the doping form to endow MoS₂ layers with negative charges, thus inducing electrostatic repulsion, together with the insertion of gaseous groups, to drive interlayer expansion which once breaks the confinement of interlayer van der Waals force, single-layered MoS₂ is obtained and uniformly dispersed into carbon matrix arising from the transformation of carbonaceous gaseous groups under high vapor pressure, is proposed. Co atom doping helps enhance the intrinsic conductivity of single-layered MoS₂ . Carbon matrix effectively prevents agglomeration of single-layered MoS₂ . The doped Co atoms can be fully transformed into ultrasmall Co nanoparticles during conversion reaction, which enables strong spin-polarized surface capacitance and thus significantly boosts ion transport and storage. Consequently, the prepared material delivers superb Li/Na/K-ion storage performances, which are best in the reported MoS₂ -based anodes. The proposed charge-driven interlayer expansion strategy provides a novel perspective for preparing single-layered MoS_2, which shows huge potential for energy storage.