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

Abstract

Abstract 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.