A novel synthesis of VSe2 as a high-rate lithium-ion battery anode material

VSe 2 is a promising anode material for Li-ion batteries (LIBs) due to its unique layered structure, and its metallic properties. However, further exploration to investigate the lithium storage performance of VSe 2 is limited by the synthesis difficulty of pure VSe 2 . In this work, a novel nitrogen-doped carbon modified VSe 2 obtained by using p -phenylenediamine as the reducing agent is reported. This material delivers a reversible capacity of 738.25 mA h g −1 at 100 mA g −1 and after 50 cycles, it retains 772.15 mA h g −1 . Using p -phenylenediamine as a reducing agent to obtain VSe 2 is demonstrated for the first time, and p -phenylenediamine also provides carbon and nitrogen sources for the heteroatom modification of VSe 2 . This modification of nitrogen-doped carbon facilitates the generation of new active sites, and improve charge transfer. First-principle calculations show that the diffusion barrier for the Li  +  migration within the VSe 2 layers is low. The ex-situ X-ray diffraction (XRD) results verify that VSe 2 stores lithium through intercalation and conversion reactions. This work may provide a new solution for synthesizing high-performance transition metal dichalcogenide electrode materials.