Carbon-supported T-Nb 2 O 5 nanospheres and MoS 2 composites with a mosaic structure for insertion-conversion anode materials.

Reasonably combining the strengths of insertion and conversion anode materials to create an advanced anode material remains a formidable challenge for rechargeable lithium-ion batteries (LIBs). In this work, bulk MoS 2 embedded with T-Nb 2 O 5 nanospheres was synthesized via a simple hydrothermal process and a polydopamine carbon source was introduced by heat treatment. The design strategy can effectively accelerate the charge transfer and reduce the volume expansion during electrochemical cycling, leading to an improvement in lithium storage performance. As a consequence, the coexistence of T-Nb 2 O 5 , MoS 2 and C can achieve the best synergistic effect when the molar ratio of Nb and Mo sources was 1 : 1. Notably, the T-Nb 2 O 5 @MoS 2 @C-1-1 electrode not only delivered an excellent reversible capacity of 518 mA h g -1 at a current density of 0.1 A g -1 but also exhibited superb cycling stability. The specific capacity of this electrode maintained 187 mA h g -1 at 2 A g -1 after 1000 cycles with a negligible capacity fading rate of only 0.015% per cycle.