Shorea robusta derived activated carbon decorated with manganese dioxide hybrid composite for improved capacitive behaviors

Autor: Armila Rajbhandari Nyachhyon, Dibyashree Shrestha, Soo Wohn Lee, Santi Maensiri, Unchista Wongpratat
Rok vydání: 2019
Předmět:
Zdroj: Journal of Environmental Chemical Engineering. 7:103227
ISSN: 2213-3437
DOI: 10.1016/j.jece.2019.103227
Popis: Shorea robusta derived activated carbon decorated with MnO 2 was successfully prepared. Thus prepared activated carbon was characterized by Thermogravimetric Analysis (TGA)/Differential Scanning Calorimetry (DSC), Scanning Electron Microscopy (SEM), X-ray diffraction ( XRD), Raman spectra, Fourier Transform Infrared Spectroscopy (FTIR), Brunauer–Emmett–Teller (BET), and X-ray Photoelectron Spectroscopy ( XPS). Results revealed that prepared material was found to be amorphous having oxygenated surface functional groups with the specific surface area 1270 m 2 g -1 ( + 0.57%). Electrochemical characterization was also performed by three electrode system where carbon electrode was used as working electrode, platinum plate was used as counter electrode and Ag/AgCl electrode was used as a reference electrode. The experiments were performed in 6 M aqueous KOH using Cyclic Voltammetry (CV), Galvanostatic Charge-Discharge (GCD) and Impendance Spectroscopy (EIS). The specific capacitance acquired from GCD at 1Ag -1 was found to be 136.3 Fg -1 ( + 0.15%) with 0.44 Ω ( + 0.02%) ESR. The 97% capacitance retention was observed after 1000 cycles. The energy density of carbon electrode was found to be 3.0 ( + 0.25%) Whkg -1 at 100.5 ( + 0.20%) Wkg -1 power density. The working carbon electrode was replaced by “hybrid composite electrode” which showed the ideal capacitive behaviors having 480.4 ( + 0.20%) Fg -1 capacitance, 24 ( + 0.26%) WhKg -1 specific energy density and low ESR value of 0.41 ( + 0.02%) Ω. The results showed that the desirable electrochemical capacitive performances enable the hybrid composite to act as a new bio material for high performance supercapacitors and energy storage devices.
Databáze: OpenAIRE