Facile synthesis of CaCo2O4/Co3O4 hexagonal nanostructure for high performance quasi-solid-state asymmetric supercapacitor

Abstract

In the present report, CaCo2O4/Co3O4 hexagonal nanostructure is prepared by facile and most adopted co- precipitation process followed by heating at 600 degrees C for 5 h. CaCo2O4/Co3O4 nanocomposite is used for super- capacitor and specific capacity of 70.28 mAh g- 1 is obtained at 1 A g- 1 using graphite sheet as a current collector. The cyclic performance of CaCo2O4/Co3O4 is investigated at 1 A g- 1 and, retention of 92.5 % is obtained after 6000 cycles. Further, quasi-solid-state asymmetric supercapacitor (QSSAC) is designed by CaCo2O4/Co3O4 (positive electrode) and activated carbon (negative electrode) which delivers the high energy density of 107.45 W h kg- 1 at the power density of 1.0 kW kg- 1. Further, parallel connected two light-emitting diodes and kitchen timer are operated separately by single CaCo2O4/Co3O4//AC supercapacitor.