Fabrication of cobalt gallium oxide with zinc iron oxide on nickel foam for a high-performance asymmetric supercapacitor.

The rational construction of advanced electrode materials with notable performances plays an essential role in the design of energy storage systems with excellent energy density and power density. In this study, for the first time, we offer a facile electrodeposition method for the synthesis of CoGa2O4 (CGO) as an advanced positive (cathode) electrode material supported on a nickel foam substrate to be used in an asymmetric supercapacitor (ASC). The CoGa2O4 (CGO)/nickel foam electrode created an efficacious and fast passageway for ion and electron transport in electrochemical process; for this reason, this electrode illustrated good electrochemical performance including excellent specific capacitance of 1379.16 F g−1 with a remarkable rate performance of 67.2% and excellent durability. Moreover, a pseudocapacitive negative electrode material of ZnFe2O4 (ZFO) was successfully deposited on a nickel foam substrate by a straightforward strategy. The as-constructed ZnFe2O4 (ZFO)/nickel foam electrode revealed a good specific capacitance of 300.5 F g−1 at 1 A g−1, satisfactory rate performance of 55.40% even at 50 A g−1 and significant durability after 6000 cycles. Due to the excellent electrochemical properties of the as-constructed pseudocapacitive electrodes, an asymmetric supercapacitor (ASC) was fabricated using CoGa2O4 (CGO)/nickel foam as an advanced positive (cathode) electrode and ZnFe2O4 (ZFO)/nickel foam as a negative (anode) electrode. The CoGa2O4 (CGO)/nickel foam//ZnFe2O4 (ZFO)/nickel foam device exhibited remarkable performance with good specific capacitance of 232.2 F g−1, excellent rate capability of 64% even at 50 A g−1, outstanding durability even after 6000 cycles and high energy density of 82.56 W h kg−1. Finally, the CoGa2O4 (CGO)/nickel foam//ZnFe2O4 (ZFO)/nickel foam device was employed to light up a blue light-emitting diode (LED), illustrating its significant potential as an advanced ASC device for the modern generation of electronic devices. [ABSTRACT FROM AUTHOR]