High performance asymmetric supercapacitor based on vertical nanowire arrays of a novel Ni@Co-Fe LDH core@shell as negative and Ni(OH) as positive electrode.

An efficient synthesis of the electrode material with abundant active sites is imperative for obtaining a flexible supercapacitor with excellent electrochemical performance. Herein, a novel flexible Ni@Co-Fe LDH core-shell nanowires supercapacitor negative electrode is synthesized using polycarbonate membrane on a copper substrate via an electrochemical deposition technique. The synthesized battery-type negative electrode exhibits remarkable specific capacitance of 1289 F g at 1 A g and excellent cycling stability with 76.66% capacitive retention after 5000 cycles. Furthermore, the Ni(OH)//Ni@Co-Fe LDH nanowires based asymmetric supercapacitor exhibits excellent cycling stability of 90.49% after 1000 cycles with a highest energy density of 68 Wh kg at 0.38 KW kg, and a good energy density of 31.8 Wh kg is still attained at a high power density of 6 KW kg. For practical demonstration, a white LED of 3.3 V is lit by using two asymmetrical supercapacitor devices connected in series. The device offers a favorable and effective pathway for advanced energy storage.