Synthesis of NiS2/reduced graphene oxide nanocomposites as anodes materials for high-performance Sodium and Potassium ion batteries

Abstract Nickel sulfide (NiS2) has displayed a widely application prospect of rechargeable batteries, solar cells, and supercapacitors. NiS2 /reduced graphene oxide nanocomposite are synthesized by a facile hydrothermal method, using polyethylene oxide-polypropylene oxide-polyethylene oxide as surfactant. Due to the synergistic effect from reduced graphene oxide and NiS 2 nanoparticles, graphene nanocomposite structure can improve the electrode conductivity and efficient buffering the volume change. As an anode material, compared with the NiS2 sample, the NiS2/reduced graphene oxide electrode exhibit excellent sodium and potassium storage properties. A first discharge capacity is 821 mAh g–1, keep in 575 mAh g–1 after 100 cycles at 100 mA g–1, and an reversible capacity of 308 mAh g–1 after 500 cycles at 5000 mA g–1 for sodium ion battery. Moreover, a reversible capacities of 320 mAh g–1 after 100 cycles at 50 mA g–1 for potassium ion battery.