High-performance asymmetric supercapacitor of sol-gel routed MgCo₂O₄/MgO microfiber

The advanced electrochemical properties, such as high specific capacitance, high energy density without scarifying the power density, fast charging–discharging rates, excellent circulation feature and low cost make the supercapacitor as a fascinating electronic device. Therefore, considerable amount of research has been devoted to enhance the electrochemical performance of the supercapacitor through the development of novel and composite electrode materials. Therefore, in this work, MgCo₂O₄/MgO composite is synthesized by a simplest sol-gel method and tissue papers are used as template to give the fibric shape to MgCo₂O₄/MgO material. The prepared MgCo₂O₄/MgO microfibers are figured out by different characteristic techniques such as XRD, FESEM, TEM, XPS and BET surface area. Further, MgCo₂O₄/MgO microfibers are subjected as electrode material for supercapacitor and high specific capacitance of 1091 F g⁻¹ is received at 1 A g⁻¹. Moreover, aqueous asymmetric supercapacitor (ASC) is designed by MgCo₂O₄/MgO microfibers (positive electrode) and activated carbon (AC) (negative electrode). The MgCo₂O₄/MgO//AC device exhibits the high energy density of 39.68 Wh kg⁻¹ at 750 W kg⁻¹. Moreover, kitchen timer, green color LEDs and a motor fan are also functionalized by two MgCo₂O₄/MgO//AC devices connected in series.