NiSe₂ Nanoparticles Decorated on Carbon Nanosheet Arrays as Anodes for Sodium Storage

As one type of promising anode for sodium-ion batteries (SIBs), nickel diselenide (NiSe2) has stimulated considerable attention. However, its wide practical application has been greatly limited by the sluggish kinetics, low electrical conductivity, as well as severe volume changes and aggregation of particles during repeated cycling. In this work, we demonstrate a facile strategy to achieve self-supporting carbon nanosheet arrays densely decorated with NiSe2 nanoparticles on carbon cloth through the one-pot hydrothermal formation of intermediate glucose-intercalated Ni(OH)2 as both the nickel precursor and carbon source, followed by carbonization and selenization processes. The strongly coupled NiSe2 nanoparticles with a carbon nanosheet matrix can endow the improved sodium storage performance owing to the robust structural integrity, abundant active sites, as well as accelerated charge transfer kinetics. As expected, the optimal anode of NiSe2/C hybrid arrays exhibits a remarkable reversible capacity of 465 mAh g–1 at a current density of 0.5 A g–1 after 350 cycles and an outstanding rate capability of 259 mAh g–1 at 5 A g–1. We propose that the present study shall unravel more insights into the delicate design and exploration of NiSe2-based anode materials for SIBs with high performance.