Supercapacitance performance of novel core/shell poly(m-toluidine)/(Co-Ni) nanoplatelets/nanoneedles nanocomposite

Poly(m-toluidine) (PmT) is a promising polymer material for many applications due to its high electrical conductivity, stability, and ease of synthesis. This work uses PmT/(Co-Ni) nanoplatelets/nanoneedles core/shell composite as an electrode for designing a high-performance supercapacitor. Firstly, nanoneedles of basic Co-Ni compounds composed of cobalt nickel oxide [CNO; Co1.29Ni1.71O4] and cobalt carbonate hydroxide hydrate [CCHH; Co(CO3)(0.5)(OH)0 center dot.11H2O] were prepared via hydrothermal process. Then, the poly(m-toluidin) [PmT; C7H9N] nanoplatelets were grown on the (Co-Ni) nanoneedles by the in-situ oxidation polymerization method. The elemental composition, crystal structure, and morphology of the PmT/(Co-Ni) electrode were characterized by physicochemical characterization techniques. The supercapacitance performance of the PmT/(Co-Ni) electrode was measured by using cyclic voltammetry, galvanostatic charge/discharge, and electrochemical impedance spectroscopy in HCl solution. The results show that the specific capacitance of the PmT/(Co-Ni) electrode was measured at a current density of 0.6 A/g reaching 308F/g. while the values of specific power density and specific energy are 720 W/kg and 15.4 W h/kg, respectively. Moreover, the PmT/(Co-Ni) electrode exhibits longterm stability and retained about 98% of its starting capacitance value after thousand cycles. The remarkable electrochemical execution recorded could be ascribed to unique nanoplatelets/nanoneedles architectures and conductive PmT polymer. These encouraging results refer to good performance and high stability of the PmT/(Co-Ni) electrode for potential application in energy storage devices.