Ti3C2Tx with a hydroxyl-rich surface for metal sulfides as high performance electrode materials for sodium/lithium storage

Abstract

Three kinds of Ti₃C₂T_x modified metal sulfide composites have been prepared via a universal one-step strategy. First, three Ti₃C₂T_x MXene supported MoS₃ composites with different surface F/O ratios and layer distances are synthesized. The abundant –OH groups on the surface of LiOH-treated Ti₃C₂T_x facilitate the effective bonding with MoS₃, forming a robust sandwich-like structure (LF/O-Ti₃C₂T_x/MoS₃). As anode material for sodium-ion batteries (SIBs), it shows outstanding long-term cycling performance in comparison with the other two Ti₃C₂T_x supported MoS₃ composites. Its reversible capacity can be maintained at 611 mA h g⁻¹ after 1000 long cycles at 2 A g⁻¹, obviously superior to those of single LF/O-Ti₃C₂T_x and MoS₃. Besides SIBs, LF/O-Ti₃C₂T_x/MoS₃ also exhibits satisfying lithium storage performance. Kinetics analysis and theoretical calculation further explain the outstanding performance of LF/O-Ti₃C₂T_x/MoS₃. Moreover, LF/O-Ti₃C₂T_x modified CuS/SnS₂ composites also show similar and excellent electrochemical results for SIBs and LIBs. This facile synthesis strategy opens a door to prepare high-performance Ti₃C₂T_x supported conversion-type anode materials for large-scale energy storage.