Solvothermal Synthesis of Nickel–Aluminum Layered Double Hydroxide Nanosheet Arrays on Nickel Foam as Binder-Free Electrodes for Supercapacitors

Abstract

Well-defined nickel–aluminum layered double hydroxide (NiAl LDH) nanosheet arrays grown on conductive nickel foam (NF) have been prepared using a facile solvothermal method and further investigated as a binder-free electrode for high-performance supercapacitors. The NiAl LDH nanosheet arrays are grown uniformly on the skeleton of the NF with a high density. Vertically-aligned nanosheets are interconnected with each other, forming highly porous wall-like structure. The NF supported NiAl LDH nanosheet arrays provide rapid electron and ion pathway, large electroactive surface area, and great structural stability. This binder-free electrode exhibits a specific capacitance of 784.1 F g−1 at 1 A g−1 and 459.6 F g−1 at 10 A g−1, respectively. Furthermore, it displays great cycling performance with 70.2% capacitance retention after 5000 cycles. The results demonstrate that the NF supported NiAl LDH nanosheet arrays can be a promising binder-free electrode for energy storage systems.