Carbon-supported T-Nb2O5 nanospheres and MoS2 composites with a mosaic structure for insertion–conversion anode materials

Abstract

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 MoS₂ embedded with T-Nb₂O₅ 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-Nb₂O₅, MoS₂ and C can achieve the best synergistic effect when the molar ratio of Nb and Mo sources was 1 : 1. Notably, the T-Nb₂O₅@MoS₂@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.