Fluorine-doped nickel-copper layered double hydroxide combined with nitrogen-doped reduced graphene oxide for high-performance asymmetric supercapacitor

An asymmetric supercapacitor (ASC) is proposed by employing fluorine-doped NiCu layered double hy-droxide (Ni4CuLDH/F) cathode and nitrogen-doped reduced graphene oxide (N-rGO) anode. The Ni4CuLDH/ F obtained a substantially dispersed structure and multiple active sites after fluorine ion doping, while the N-rGO achieved crimped graphene layers and additional pseudocapacitive properties after nitrogen doping. The Ni4CuLDH/F prepared by a low-temperature titration method displayed a considerable specific capa-citance of 1780 F g-1 at a current density of 1 A g-1. Also, the capacitance of the hydrothermally prepared N-rGO intensified from 287 F g-1 to 392 F g-1 at 1 A g-1 with a wider potential window. Besides, an ASC based on the two electrodes presented an outstanding energy density of 54.0 Wh kg-1 at a power density of 375 W kg-1 with distinguished cycling capability (59% retention over 10000 cycles). Overall, the ASC reveals a tremendous possibility for practical implementation in the arena of high-performance supercapacitors.(c) 2022 Elsevier B.V. All rights reserved.