Nickel sulfide/nickel phosphide heterostructures anchored on porous carbon nanosheets with rapid electron/ion transport dynamics for sodium-ion half/full batteries.

[Display omitted] Nickel-based materials have been extensively deemed as promising anodes for sodium-ion batteries (SIBs) owing to their superior capacity. Unfortunately, the rational design of electrodes as well as long-term cycling performance remains a thorny challenge due to the huge irreversible volume change during the charge/discharge process. Herein, the heterostructured ultrafine nickel sulfide/nickel phosphide (NiS/Ni 2 P) nanoparticles closely attached to the interconnected porous carbon sheets (NiS/Ni 2 P@C) are designed by facile hydrothermal and annealing methods. The NiS/Ni 2 P heterostructure promotes ion/electron transport, thus accelerating the electrochemical reaction kinetics benefited from the built-in electric field effect. Moreover, the interconnected porous carbon sheets offer rapid electron migration and excellent electronic conductivity, while releasing the volume variance during Na+ intercalation and deintercalation, guaranteeing superior structural stability. As expected, the NiS/Ni 2 P@C electrode exhibits a high reversible specific capacity of 344 mAh g−1 at 0.1 A g−1 and great rate stability. Significantly, the implementation of NiS/Ni 2 P@C//Na 3 (VPO 4) 2 F 3 SIB full cell configuration exhibits relatively satisfactory cycle performance, which suggests its widely practical application. This research will develop an effective method for constructing heterostructured hybrids for electrochemical energy storage. [ABSTRACT FROM AUTHOR]