Nickel-Sulfide/Vanadium-Sulfide/Carbon Composite Nanofibers for Lithium-Ion Storage

Vanadium-sulfide-based materials, known for their structural diversity, multielectron redox capability, and cost-effectiveness, have emerged as prospective anodic materials for advanced lithium-ion batteries (LIBs). However, the drawbacks of poor structural stability and significant kinetic sluggishness greatly hinder their practical implementation. Here, a three-dimensional network heterostructured nickel-sulfide/vanadium-sulfide/carbon composite was successfully fabricated, which was formed by irregular NiS2/VS4 nanoparticles tightly anchored to the cellulose-derived carbon fibers (CFs). Simultaneously, the nanofibrous NiS2/VS4/CF composite effectively suppressed the aggregation of the bimetallic sulfide nanoparticles during the lithiation and delithiation process when applied as an anodic material for LIBs, significantly mitigated volume expansion during cycling, and remarkably enhanced electronic/ionic transport across the entire electrodes. The NiS2/VS4/CF composite delivered a high discharge capacity of 938.6 mAh g–1 at 0.1 A g–1 and a fast-rate capability of 642.3 mAh g–1 at 2 A g–1. Kinetic analysis demonstrated that the three-dimensional network heterostructure of the composite contributed to the formation of a stable solid electrolyte interphase and a charge transfer interface, facilitating electron transfer and ion transport, underscoring the essential role of structural adjustment to achieve an effective lithium storage property. This work presents a facile and cost-effective pathway to synthesize cellulose substance-derived nanocomposite materials for energy applications.