The combination of structure designs at the microscopic and macroscopic level can efficiently enable electrode materials with greatly enhanced lithium and sodium storage. In this paper, the construction of Ni2P/NiS0.66 heterostructures and their assembly into a superstructure at the nanoscale were successfully achieved by a facile and effective strategy. In the obtained superstructure, the Ni2P/NiS0.66 heterostructures are homogeneously coated with ultrathin carbon layers (HT-NPS@C) and, at the same time, assembled into a yolk-shell nanosphere. Upon evaluation as the anode materials for Li-ion batteries, the HT-NPS@C delivers a high reversible capacity of 430 mA h g-1 after 200 cycles at 200 mA g-1 and ultrastable cyclability with negligible capacity loss over 500 cycles. Furthermore, the coin-type full cell with the LiNi1/3Co1/3Mn1/3O2 (LNCMO) cathode and HT-NPS@C anode deliver a high specific capacity of 323.5 mA h g-1 after 50 cycles at 0.3 A g-1. Apart from an excellent performance as promising anode materials for LIBs (Li-ion batteries), the Na-ion batteries with HT-NPS@C sphere electrodes also manifest a remarkable electrochemical performance.
Keywords: Li-ion battery; Na-ion battery; heterostructures; nanocrystals; sulfur dopant; superstructure.