Design and facile synthesis of nitrogen-doped carbon decorated LiVPO4F nanocrystals as superior cathode for lithium-ion batteries

Abstract

In this study, nitrogen-doped carbon is coated on LiVPO4F electrode for the first time via a simple chemical refluxing process, using ethylenediamine (EDA) as the carbon and nitrogen source. The structure, morphology and microstructure of the as-prepared electrode are characterized by XRD, XPS, Raman spectra, SEM and TEM. The uniform coating of nitrogen-doped carbon improves the electronic conductivity of LiVPO4F. As cathode material for lithium-ion batteries, the nitrogen-doped carbon coated LiVPO4F composite exhibits superior rate capability and excellent cycle performance over the carbon coated LiVPO4F. The electrode delivers an initial discharge capacity of 109.6mAhg−1 at high rate of 10C and 103.1mAhg−1 of capacity is retained after 100cycles. Thus, this novel modification method of nitrogen-doped carbon coating is highly effective and could be widely used to optimize the electronic conductivity of other electrode materials for lithium-ion batteries.