Nitrogen-doped carbon coated Li3V2(PO4)3 derived from a facile in situ fabrication strategy with ultrahigh-rate stable performance for lithium-ion storage

Abstract

A nitrogen-doped carbon coated Li₃V₂(PO₄)₃ cathode material is prepared by using a very simple in situ approach. The Li₃V₂(PO₄)₃ particle is uniformly encapsulated by a nitrogen-doped carbon layer, where a carbon coating layer exists, nitrogen-doping also exists. N-doping on the carbon layer significantly increases the electronic conductivity of as-prepared Li₃V₂(PO₄)₃ sample, and thus, this Li₃V₂(PO₄)₃/C+N demonstrates ultrahigh rate performance and excellent cycling stability for lithium storage. When the discharging rate is increased from 0.5 C to 50 C, its capacity of 119.5 mA h g⁻¹ decays to 110.8 mA h g⁻¹ and an amazing capacity retention of 93% is achieved. This in situ synthetic approach of a nitrogen-doped carbon coated Li₃V₂(PO₄)₃ cathode reported herein is highly efficient and easily realized in industrial applications and moreover, is able to be extended to modify other electrode materials in which carbon-coating is indispensable, such as LiFePO₄etc.