3D network and wrapping strategy derived loofah-like Sb@CNTs@C for high performance K+/Na+ storage

Antimony (Sb) has an ultra-high theoretical specific capacity and is a very promising anode material for potassium-ion batteries (PIBs) and sodium-ion batteries (SIBs). In this paper, carbon coated carbon nanotubes (CNTs) and Sb (Sb@CNTs@C) nanomaterials were efficaciously synthesized by way of a one-step solvothermal and thermal reduction method. As the anode material of PIBs, Sb@CNTs@C has decent electrochemical performance and good cycle stability. The initial charge specific capacities at 0.2 A g−1 is 974 mAh g−1. Even at 1 A g−1, 206 mAh g−1 is retained after 1000 cycles. As the anode material of SIBs, the Sb@CNTs@C exhibited a charging capacity of 221 mAh g−1 at 0.2 A g−1 after 1000 cycles. The loofah-like Sb@CNTs@C nanomaterial has good electrochemical properties, which is mainly due to the formation of a 3D network structure by Sb, CNTs and carbon coating. In response to the volume expansion problem of Sb in K+/Na+ storage, the loofah-like Sb@CNTs@C has constructed a good conductive network, provided sufficient volume expansion space, and also formed an effective protective layer.