Preliminary Study of the Specific Capacitance of Supercapacitor Electrode Prepared from Carbonized Bituminous Raw Coal Mohamad Samsul Anrokhi (a), Oktaviardi Bityasmawan Abdillah(a), Pipit Fitriani (a,b), Fatimah Arofiati Noor (a), and Ferry Iskandar (a*,b)
(a) Physics of Electronic Materials Research Group, Dep. of Physics, FMIPA ITB
(b) Reseach Center of Nanosceinece and nanotechnology (RCNN),
Institut Teknologi Bandung. Bandung, Indonesia.
Email: ferry[at]itb.ac.id
Abstract
A bituminous grade coal is promising and cost-effective raw material for supercapacitor electrodes application. Carbonization plays a crucial role in transforming the organic components present in raw coal into a carbon-rich structure with an enhanced capacity for charge storage. In this research, we study the specific capacitance of electrode prepared from the carbonized bituminous coal as a preliminary evaluation of its electrochemical properties. The carbonized bituminous coal was synthesized through a simple heat treatment at temperatures of 7000C and 9000C under a continuous flow of argon gas for 2 hours. The structural behavior of carbonized bituminous coal was analyzed using several characterizations, including Raman spectroscopy, x-ray diffraction (XRD), and Fourier transform infrared (FTIR) spectroscopy. Furthermore, the electrochemical properties were evaluated using cyclic voltammetry (CV) and galvanostatic charge discharge in a 3 M electrolyte solution of potassium hydroxide (KOH) with a three-electrodes configuration. The specific capacitances of 49.75 Fg-1 and 20.00 F g-1 at a current density of 0.5 Ag-1 were achieved for the sample produced at the carbonization temperature of 7000C and 9000C, respectively. These values are considerably higher than the specific capacitance of raw bituminous coal (0.687 F g-1) at 0.5 Ag-1. This result may offer valuable insight for the further development of coal-based supercapacitor electrodes.
Keywords: Coal, carbonization, specific capacitance