VN Quantum Dots Embedded in N-Doped Carbon for High-Performance Lithium Storage
Chunyan Tang, Huachao Tao, Xinyu Liu, Xuelin Yang
Abstract
Vanadium nitride (VN) with a high theoretical specific capacity and electronical conductivity is a potential material for lithium-ion batteries (LIBs). Regrettably, the large volume changes and slow Li+ diffusion kinetics lead to a rapid attenuation of capacity and poor rate capability. Therefore, a vanadium nitride/N-doped carbon (VN/NC) nanocomposite has been prepared through a simple and one-step method. The N-doped carbon framework is evenly inserted with vanadium nitride (VN) quantum dots. The VN/NC nanocomposite can provide up to 755 mAh g–1 of special capacity after 200 cycles at 0.1 A g–1 and 396 mAh g–1 after 1000 cycles at 1.0 A g–1 in LIBs. Based on a LiNi0.33Co0.33Mn0.33O2 (NCM) cathode and a VN/NC anode, the full cell also exhibits a desirable capacity of 320 mAh g–1 after 350 cycles at 1.0 A g–1. The reason for such good electrochemical properties is that VN quantum dots provide high capacity and N-doped carbon acts as a conductive network and mechanical support.