Enhancing supercapacitive performance: integration of bio-mass-derived carbon into a CaMn3O6 nanocomposite

A metal oxide consisting of calcium and manganese (CaMn3O6) in a spherical architecture was successfully prepared by a simple hydrothermal method. Subsequently, Ipomoea carnea-derived carbon (IC) was synthesized and a nanocomposite with CaMn3O6 was formed. The pure CaMn3O6 exhibited a higher surface area of 111 m2 g−1 and CaMn3O6/IC showed a surface area of 101 m2 g−1 with enhanced pore volume, which was desirable in delivering better capacitance. The electrode materials were tested in both three-electrode and two-electrode systems in which CaMn3O6 delivered a capacitance of 294 F g−1 and CaMn3O6/IC delivered a capacitance of 414 F g−1. Furthermore, on fabricating a pouch-cell type asymmetric supercapacitor, CaMn3O6‖AC device showed a capacitance of 76 F g−1 and CaMn3O6/IC‖AC device delivered a capacitance of 116 F g−1. In addition, the CaMn3O6/IC‖AC device showed superior stability and capacitance retention, which can be associated with the presence of an IC matrix. Utilizing the CaMn3O6/IC‖AC pouch-cell device, an LED bulb was operated to test for real-time applications.