Investigation and fabrication of asymmetrical supercapacitor using nanostructured Mn_3O_4 immobilized carbon nanotube composite

摘要

The manganese oxide (Mn_3O_4) nanoparticles (NPs) were immobilized in the surface of functionalized carbon nanotubes (fCNT) (Mn_3O_4-fCNT composite) for the enhancement of electrochemical performances. The broad and notable crystalline peaks were found in a powder X-ray diffraction pattern of Mn_3O_4-fCNT and it confirms that, Mn_3O_4 presence in nanoscale. The functional vibrations of -OH, -COOH, C=O, C-O were found in FTIR spectrum and Raman spectra also recorded to understand functional groups present in the composite. The surface morphology was studied and also, the elemental analysis was carried out for Mn_3O_4-fCNT using SEM images of the composite. The electrochemistry responses of Mn_3O_4-fCNT were investigated. We have evaluated its response and performances in cyclic voltammetry, impedance, galvano- static charge-discharge aspects. A notable specific capacitance of 499 Fg~(-1) at 0.1 mAg~(-1) was found in Mn_3O_4-fCNT. The asymmetrical supercapacitor was designed with Mn_3O_4-fCNT and ZnO-CNT and its specific capacitance was evaluated.