MoS₂/TiO₂ Heterostructures In Situ Constructed on Mo₂Ti₂C₃T_<i>x</i> MXene for High-Rate and Stable Li⁺/Na⁺ Storage

Out-of-plane ordered Mo₂Ti₂C₃T_<i>x</i> 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 Mo₂Ti₂C₃T_<i>x</i> MXene were cleverly modified by the hydrothermal method at 250 °C and a sulfur-containing atmosphere, while MoS₂/TiO₂ heterostructures were in situ constructed on Mo₂Ti₂C₃T_<i>x</i> MXene. The as-prepared Mo₂Ti₂C₃T_<i>x</i>@MoS₂/TiO₂ hybrids deliver excellent lithium/sodium storage properties, especially outstanding rate properties and robust cycling stability. At 5 A g^–1, Mo₂Ti₂C₃T_<i>x</i>@MoS₂/TiO₂ 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.