Zn-Ni-Co trimetallic carbonate hydroxide nanothorns branched on Cu(OH)2 nanorods array based on Cu foam for high-performance asymmetric supercapacitors

Here we report the development of a high-performance electrode material composed of Zn and Ni co-substituted Co carbonate hydroxide (ZnNi-Co-2(CO3)(OH)(2)) nanothorns branched on Cu(OH)(2) nanorods array (Cu(OH)(2)@ZnNi-Co-2(CO3)(OH)(2)), which are grown directly on copper foam current collector. The electrode materials are obtained by a simple in situ oxidation reaction and a hydrothermal strategy. The as-obtained Cu(OH)(2)@ZnNi-Co-2(CO3)(OH)(2) electrode exhibits significantly enhanced electrochemical performance with a high specific capacitance (2746 F g(-1) at 1 A g(-1)), and extraordinary cycling stability (maintained 95.61% of the initial capacitance after 6000 cycles at 20 A g(-1)), which are much superior to those of Cu(OH)(2), Cu(OH)(2)@ Co-2(CO3)(OH)(2), Cu(OH)(2)@Ni-Co-2(CO3)(OH)(2), and bare ZnNi-Co-2(CO3)(OH)(2) nanospheres electrodes. Additionally, the Cu(OH)(2)@ZnNi-Co-2(CO3)(OH)(2) nanorods array can also be utilized as the positive electrode to fabricate an asymmetric supercapacitor device with an active carbon negative electrode, realizing a high cell voltage of 1.5 V and the energy density of up to 34.75Wh kg(-1) at a power density of 375 W kg(-1). The excellent electrochemical properties can be credited to the three-dimensional hierarchical core-shell architecture.