Carbon-coated Ni(OH)2-NiAl LDH hierarchical nanostructures on Ni foam as a high areal capacitance electrode for supercapacitor application

In this work, carbon-coated Ni(OH)2/NiAl layered double hydroxide hierarchical nanostructures (Ni(OH)2/NiAl-LDH@C) in situ grown on Ni foam are synthesized by integrating an atomic layer deposition (ALD) technique with a simple hydrothermal treatment. Such a unique hierarchical structure provides areal capacitance as high as 14.0 F cm−2 at 5 mA cm−2 with excellent rate capability (8.09 F cm−2 at 50 mA cm−2), and maintains 87.2% of the initial capacitance even after 2000 cycles. These excellent electrochemical performances demonstrate that the binder-free Ni(OH)2/NiAl-LDH@C as battery-like electrode has great competitiveness for supercapacitors in future energy storage applications.