Controllable Design of MoS₂ Nanosheets Grown on Nitrogen-Doped Branched TiO₂/C Nanofibers: Toward Enhanced Sodium Storage Performance Induced by Pseudocapacitance Behavior

In this work, expanded MoS₂ nanosheets grown on nitrogen-doped branched TiO₂/C nanofibers (NBT/C@MoS₂ NFs) are prepared through electrospinning and hydrothermal treatment method as anode materials for sodium-ion batteries (SIBs). The continuous 1D branched TiO₂/C nanofibers provide a large surface area to grow expanded MoS₂ nanosheets and enhance the electronic conductivity and cycling stability of the electrode. The large surface area and doping of nitrogen can facilitate the transfer of both Na⁺ ions and electrons. With the merits of these unique design and extrinsic pseudocapacitance behavior, the NBT/C@MoS₂ NFs can deliver ultralong cycle stability of 448.2 mA h g⁻¹ at 200 mA g⁻¹ after 600 cycles. Even at a high rate of 2000 mA g⁻¹, a reversible capacity of 258.3 mA h g⁻¹ can still be achieved. The kinetic analysis demonstrates that pseudocapacitive contribution is the major factor to achieve excellent rate performance. The rational design and excellent electrochemical performance endow the NBT/C@MoS₂ NFs with potentials as promising anode materials for SIBs.