Synthesis of nanosheet-like α-Ni(OH)2/g-C3N4 hybrid anode material with enhanced lithium storage performance

Abstract

Nickel hydroxide (Ni(OH)2) has been recognized as a promising anode material for lithium-ion batteries (LIBs) because of its high theoretical capacity, cost-effectiveness, and simple synthesis method. However, the application of Ni(OH)2 is hampered by its volume effect and poor electrical conductivity. To address these challenges, herein, a α-Ni(OH)2/g-C3N4 composite is prepared by a hydrothermal approach. The composite possesses a hierarchical nanosheet-like morphology with fibrous nanostructures on the surface. Due to the unique hybrid nanostructure and the synergistic effect of α-Ni(OH)2 and g-C3N4 components, the α-Ni(OH)2/g-C3N4 composite exhibits significantly enhanced lithium storage performance in terms of electrochemical activity, cyclability, and kinetics than the bare α-Ni(OH)2 counterpart. Specifically, the α-Ni(OH)2/g-C3N4 achieves a remarkable capacity of 696 mA h g−1 after 400 cycles at 0.5 A g−1, far larger than the corresponding value (96 mA h g−1) of pure α-Ni(OH)2. CV and GITT analysis demonstrate the α-Ni(OH)2/g-C3N4 composite has an obvious pseudocapacitance behavior and a much smaller polarization effect than the bare α-Ni(OH)2 during cycling. This work could provide clues for the structural design and performance improvement of nickel hydroxide-based anode materials for LIBs.