Anion-Cation Co-Electron Modulation Enabled 1T Phase Transition in MoS₂ for Ultra-Fast Sodium Ion Storage

Although metastable 1T-MoS₂ boasts advantages such as high electrical conductivity, rapid ion diffusion, and high capacity, its thermodynamic instability and stringent synthesis conditions impede practical applications. Addressing the core of phase regulation in MoS_2-the electronic states of the Mo 4d orbitals-a synergistic electron modulation strategy utilizing Cu²⁺/ ${\mathrm{PO}}_4^{3-}$ cations and anions was employed to successfully anchor highly stable 1T-MoS₂ (CP-MoS₂@rGO) onto a reduced graphene oxide (rGO) substrate. The Cu²⁺/ ${\mathrm{PO}}_4^{3-}$ ions induce a charge redistribution that drives the reorganization of Mo 4d orbitals. Concurrently, the interlayer intercalation support effect of ${\mathrm{PO}}_4^{3-}$ expands the interlayer spacing, which effectively suppresses topological phase transitions during the sodiation/desodiation process, thereby achieving kinetic stabilization of the metastable 1T phase. Benefiting from this unique structural design, the CP-MoS₂@rGO exhibits exceptional rate capability (372.5 mAh g^-1 at 24 A g^-1) and an ultra-long cycle life (stable cycling for over 8000 cycles at a current density of 18 A g^-1), along with highly reversible structural reconstruction. This work establishes a new paradigm for the rational design and stabilization of metastable 1T-MoS₂-based materials for advanced energy storage applications.