Ni2P nanoparticle-incorporated reduced graphene oxide & carbon nanotubes to form flexible free-standing intertwining network film anodes for long-life sodium-ion storage.

In this paper, Ni₂P nanoparticles is incorporated onto the graphene & carbon nanotubes composite (Ni₂P NPs/rGO & CNTs) to form flexible free-standing intertwining network film anodes for improving the cycle-life of sodium-ion batteries (SIBs). Benefited from the volume accommodation by this Ni₂P NPs/rGO & CNTs structure and its excellent electronic conductive network along with high mechanical strength, such an anode-based SIB shows a superior capacity retention with a stable and long cycle-life at high current densities. For Ni₂P NPs/rGO & CNTs electrode, it remains a capacity of 224 mAh g⁻¹ after 100 cycles, at a high current density of 0.5 A g⁻¹, the Ni₂P NPs/rGO & CNTs can still maintain a stable reversible capacity of ~ 150 mAh g⁻¹ after 500 cycles, after cycling at a rate as high as 1 A g⁻¹, the reversible capacity of the Ni₂P NPs/rGO/CNT can still sustain stable capacities at 91 mAh g⁻¹ after 2000 cycles, respectively. Even at 5 A g⁻¹, it still exhibits a high rate capacity of 65 mAh g⁻¹, thus exhibiting an excellent sodium storage kinetics. [ABSTRACT FROM AUTHOR]