High performance asymmetric supercapacitor based on vertical nanowire arrays of a novel Ni@Co–Fe LDH core@shell as negative and Ni(OH) 2 as positive electrode

Abstract 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 −1 at 1 A g −1 and excellent cycling stability with 76.66% capacitive retention after 5000 cycles. Furthermore, the Ni(OH) 2 //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 −1 at 0.38 KW kg −1 , and a good energy density of 31.8 Wh kg −1 is still attained at a high power density of 6 KW kg −1 . 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.