MoS₂/TiO₂ Heterostructures In Situ Constructed on Mo₂Ti₂C₃T_x MXene for High-Rate and Stable Li⁺/Na⁺ Storage

Out-of-plane ordered Mo 2 Ti 2 C 3 T x MXene is composed of M-site binary metals with richer structural compositions and physicochemical properties, thus becoming a potential candidate for energy storage materials. Here, the microstructures of pre-etched Mo 2 Ti 2 C 3 T x MXene were cleverly modified by the hydrothermal method at 250 °C and a sulfur-containing atmosphere, while MoS 2 /TiO 2 heterostructures were in situ constructed on Mo 2 Ti 2 C 3 T x MXene. The as-prepared Mo 2 Ti 2 C 3 T x @MoS 2 /TiO 2 hybrids deliver excellent lithium/sodium storage properties, especially outstanding rate properties and robust cycling stability. At 5 A g –1, Mo 2 Ti 2 C 3 T x @MoS 2 /TiO 2 provides reversible Li + (377.8 mAh g –1 )/Na + (133.5 mAh g –1 ) storage capacity. Capacity preservation reaches 83.7%/74% over 4500/30,000 cycles in LIBs/SIBs. This paper highlights the importance of rational structural modification by utilizing the rich metal compositions of M-sites in MXene, effectively enhancing its lithium/sodium storage capacity and broadening the further application of double transition metal MXene in secondary batteries.