Ultrathin Ni-Al layered double hydroxide nanosheets with enhanced supercapacitor performance

Abstract To improve electrochemical energy storage performance of Ni-Al layered double hydroxide (Ni-Al LDH) as supercapacitor electrode, ultrathin Ni-Al LDH nanosheets were prepared by simple hydrothermal method. The surface area of the ultrathin structure with broad pore size distribution is high to 64.9 m 2 g −1 . The ultrathin Ni-Al LDH nanosheets exhibit excellent pseudocapacitance performance with a maximum specific capacitance of 1919 F g −1 and a capacity retention of 433 F g −1 after 3000 cycles at a current density of 2 A g −1 . Furthermore, a reversible capacity of 1665 F g −1 was obtained at a much higher current density of 30 A g −1 . The fascinating performances can be attributed to the improvement of pseudocapacitive reaction by the ultrathin structure of Ni-Al LDH. The impressive results may pave the way for promising applications in high energy density storage systems.