Shorea robusta derived activated carbon decorated with manganese dioxide hybrid composite for improved capacitive behaviors. Issue 5 (October 2019)

• Record Type: Journal Article
• Authors: Shrestha, Dibyashree; Maensiri, Santi; Wongpratat, Unchista; Lee, Soo Wohn; Nyachhyon, Armila Rajbhandari
• Is Part Of: Journal of environmental chemical engineering. Volume 7:Issue 5(2019)
• Publication Date: 2019-10
• Subjects: Hybrid composite -- Capacitive behavior -- Energy density -- Power density; Chemical engineering -- Environmental aspects -- Periodicals; Environmental engineering -- Periodicals; Chemical engineering -- Environmental aspects; Environmental engineering; Periodicals; 660.0286
• DOI: 10.1016/j.jece.2019.103227
• Languages: English
• ISSNs: 2213-2929

Abstract

Graphical abstract: Highlights: Shorea robusta derived activated carbon decorated with manganese dioxide hybrid composite (Sa-H3 PO4 :MnO2 ) has been prepared. Low resistivity with elevated specific capacitance behaviors was observed. 1:1 composition of (Sa-H3 PO4 :MnO2 ) displayed very high energy density and power density. Results revealed that H3 PO4 acid activated carbon along with MnO2 is the potential candidate for the supercapacitors. Abstract: Shorea robusta derived activated carbon decorated with MnO2 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 1 Ag −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%) W h kg −1 at 100.5 (±0.20%) W kg −1 power density. The working carbon electrode was replaced by "hybrid composite electrode" which showed the ideal capacitive behaviors having 480.4 (±0.20%) F g −1 capacitance, 24 (±0.26%) W h kg −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.