In situ synthesis of CNTs@Ti3C2 hybrid structures by microwave irradiation for high-performance anodes in lithium ion batteries

Abstract

To stabilize the layer structures of MXenes, carbon nanotubes (CNTs) have been successfully grown in situ by a facile microwave irradiation method under ambient conditions. The synthesized composites based on various MXenes including Ti₃C₂, Ti₂C and V₂C exhibited hybrid structures with uniformly distributed multi-walled CNTs anchored on the layer structured MXene networks. Benefiting from the unique structural features, these composites exhibit excellent electrochemical properties as anode materials in lithium ion batteries. The CNTs@Ti₃C₂ composite exhibits high reversible capacities of 430 mA h g⁻¹ at 1 A g⁻¹ and 175 mA h g⁻¹ at 10 A g⁻¹ (31.25 C), and is not only better than the pristine Ti₃C₂ (99 mA h g⁻¹ and 45 mA h g⁻¹, respectively), but also superior to the recently reported MXene composites. The impressive electrochemical performance is attributed to the synergetic effects of the connective CNT bridges, large-capacity metal/metal oxides and the fine conductive MXene matrix. This in situ growth strategy of CNTs shows great potential in modulating the structure and properties of nanomaterials for advanced applications.