B, N-Co-doped Carbon Tubes with P Encapsulated in 3D Graphene Aerogel for High-stable Lithium-ion Batteries

Abstract

Li-related anodes with stable ability and excellent rate performance are urgently being pursued to overcome the slow kinetic of current lithium ion storage devices. In this work, an annealing-hydrothermal method is developed to fabricate the anode of a three-dimension nano-construction with robust charge transfer networks, which is composed of elements B, N co-doped carbon tube (BN-CT) as the carrier of red phosphorous to (3D BN-CT@P). Then, 3D BN-CT@P is embedded in the graphene aerogel network to obtain 3D BN-CT@P@GA). Impressively, the 3D BN-CT@P@GA shows high capacity and good cycle stability in the potential rage of 0.01-2.5V. Especially, the discharge capacity is ~800 mAh g-1 at 500 mA g-1 after 500 cycles when evaluated as anode materials for lithium-ion batteries (LIBs). The improved electrochemical performances result from the unique structure of the 3D BN-CT@P@GA. With the hetero atoms doping, the active P can load up to the BN-CT, which can realize the high capacity as well as the low potential for the anode. At the same time, the graphene aerogel network provides the protection for the BN-CT@P species and good conductivity to enhance ion diffusion. This work fundamentally presents an effective structural engineering way for improving the performance of P-based anodes for advanced LIBs.