Robust pseudocapacitive charge storage behavior in Li3VO4 induced by N doped MXene

In/Ce Co-doped Li3VO4 and Nitrogen-modified Carbon Nanofiber Composites as Advanced Anode Materials for Lithium-ion Batteries

Li₃VO₄ (LVO) is considered as a novel alternative anode material for lithium-ion batteries (LIBs) due to its high capacity and good safety. However, the inferior electronic conductivity impedes its further application. Here, nanofibers (nLICVO/NC) with In/Ce co-doped Li₃VO₄ strengthened by nitrogen-modified carbon are prepared. Density functional theory calculations demonstrate that In/Ce co-doping can substantially reduce the LVO band gap and achieve orders of magnitude increase (from 2.79 × 10^-4 to 1.38 × 10^-2 S cm^-1) in the electronic conductivity of LVO. Moreover, the carbon-based nanofibers incorporated with 5LICVO nanoparticles can not only buffer the structural strain but also form a good framework for electron transport. This 5LICVO/NC material delivers high reversible capacities of 386.3 and 277.9 mA h g^-1 at 0.1 and 5 A g^-1, respectively. Furthermore, high discharge capacities of 335 and 259.5 mA h g^-1 can be retained after 1200 and 4000 cycles at 0.5 and 1.6 A g^-1, respectively (with the corresponding capacity retention of 98.4 and 78.7%, respectively). When the 5LICVO/NC anode assembles with commercial LiNi_1/3Co_1/3Mn_1/3O₂ (NCM111) into a full cell, a high discharge capacity of 191.9 mA h g^-1 can be retained after 600 cycles at 1 A g^-1, implying an inspiring potential for practical application in high-efficiency LIBs.