Facile synthesis of ultrathin nickel hydroxides nanoflakes on nickel foam for high-performance supercapacitors

• Ultrathin Ni(OH)2 nanoflakes were prepared via a facile hydrothermal route.
• Nickel foam acts as substrate and provides the nickel sources of Ni(OH)2.
• Binder-free Ni(OH)2 electrode shows excellent electrochemical performance.
• The performance is ascribed to unique structure of nanoflakes.

Ultrathin Ni(OH)2 nanoflakes grown on nickel foam have been prepared via a facile hydrothermal route without adding any additional nickel sources and further investigated as a binder-free electrode for high-performance supercapacitors. Benefiting from high conductivity and enough spaces between the nanoflakes in combination with high surface area, the Ni(OH)2 nanoflakes show high-capacitance performance with a specific capacitance of 2342 F g−1 at a charge and discharge current density of 2 mA cm−2 and 1100 F g−1 at 8 mA cm−2 with a good cycling ability (80.4% of the initial specific capacitance remains after 2000 cycles). These results show that Ni(OH)2 nanoflakes with this cost-effective synthesis route and distinguished electrochemical performance combined with the flexible nickel foam substrate are very promising for the next generation of high-performance supercapacitors.

Ultrathin Ni(OH)2 nanoflakes grown on nickel foam have been prepared via a facile hydrothermal route without adding any additional nickel sources and further investigated as a binder-free electrode for high-performance supercapacitors. In this easy and controllable method the nickel foam not only acts as 3D substrate but also provides the nickel sources of ultrathin Ni(OH) nanoflakes, allowing direct contact with nickel foam and easy access to electrolyte and facilitating the transport and diffusion of electrons and ions in the electrode, respectively. Benefiting from this unique structure, the Ni(OH)2 nanoflakes show excellent electrochemical performance with a good cycling ability at 8 mA cm−1 (80.4% of the initial specific capacitance remains after 2000 cycles). The results show that Ni(OH)2 nanoflakes with this cost-effective synthesis route and distinguished electrochemical performance combined with the flexible nickel foam substrate are very promising for the next generation of high-performance supercapacitors.Figure optionsDownload as PowerPoint slide