No abstract

Ni-based selenide has flourished as one of the most competitive anode materials for sodium-ion batteries due to its low cost, wide source, and high theoretical specific capacity. As one of the members, NiSe microparticles with the sizes of 2.0−10.6 μm are synthesized with disused nickel foam fragments by a facile and rapid one-step selenization method, possessing a prominent rate capability of 304.3 mAh g −1 at 15 A g −1 and a remarkable lifespan with 291.7 mAh g −1 after 1600 cycles at 2 A g −1 . A Na 3 V 2 (PO 4 ) 2 F 3 @reduced graphene oxide//NiSe full cell also exhibits excellent sodium storage behavior and potential utility, achieving the largest power density of 1919.0 W Kg −1 , the highest energy density of 146.0 Wh kg −1 , and a capacity of 119.7 mAh g −1 after 600 cycles at 1 A g −1 accompanied by impressive Coulombic efficiency (>95%, except for the first two cycles). The reversible phase transition, proper use of the ether electrolyte, low electrochemical impedance, and favorable structural stability all synergistically contribute to the satisfactory electrochemical property of NiSe. This work effectively improves the preparation efficiency of NiSe, tendering a new synthetic route for the anode materials.