Construction of hierarchical Cu2+1O@NiCoAl-layered double hydroxide nanorod arrays electrode for high-performance supercapacitor

Here we report the construction of a kind of electrode material with excellent capacitive performance composed of Ni, Co and Al layered double hydroxide (NiCoAl-LDH) nanosheets branched on Cu2+1O nanorod arrays (Cu2+1O@NiCoAl-LDH) on copper foam current collector, which is obtained via an easy in situ chemical oxidation reaction in combination with hydrothermal method. The as-prepared Cu2+1O@NiCoAl-LDH electrode presents observably enhanced electrochemical performance with an outstanding specific capacitance (2932 F g(-1) at 0.75 A g(-1)), and extraordinary cycling stability (94.27% of the initial capacitance maintained after GCD test for 6000 cycles), which are much superior to those of Cu(OH)(2)and Cu2+1O@NiCo-LDH electrodes. Additionally, the Cu2+1O@NiCoAl-LDH nanorod arrays, as a positive electrode material, can also be utilized to assemble a hybrid supercapacitor (HSC) device with an activated carbon (AC) electrode (negative electrode). The energy density of the assembled HSC device can up to 61.83 Wh kg(-1) with a working voltage of 1.5 V, meanwhile the power density is 749.93 W kg(-1). Furthermore, a few Light Emitting Diode (LED) indicators with different shape combination can be lit up by the assembled HSC devices, demonstrating the practicability of the HSC device. (C) 2020 Elsevier B.V. All rights reserved.