Supercapacitor carbon electrodes from pyrolyzed glycerol
In this study pyrolyzed glycerol was explored as electrode material using a catalytic agent during pyrolysis. Here, evaporation of glycerol at high temperatures was prevented by catalyzing the formation of oligoglycerol in turn leading to carbonization above 300 °C. A one-step and tow-step pyrolysis process were developed and compared based on the suercapacitive properties of the carbon material. The pyrolysis of the glycerol was performed at 600 °C for 1 hour under nitrogen atmosphere. The product obtained was washed with 1 M HCl, and characterized using scanning electron microscopy (SEM), nitrogen adsorption (BET surface analysis), Fourier transform infrared (FTIR) spectroscopy, cyclic voltammetry, and galvanostatic charge-discharge measurements. Carbon percent yields of 4-6% were obtained for the two different processes. The one-step process was found to have slightly higher yields. FTIR spectroscopy showed that majority of the functional groups had been removed during the pyrolysis process. SEM images show no significant difference in the surface morphology and porosity from the products of the two processes. Fabricated electrodes showed specific capacitances ranging from 0.25 Fg"-“1 to 1.36 Fg"-“1 through cyclic voltammetry in 1 M Li_2SO_4 with a sweep rate of 100 mV s”-“1 and galvonostatic cycling with a current of 1 and 5 mA from 0 to 1.2 V. These results show the potential use of carbon from pyrolysis of glycerol as active component in carbon-based supercapacitors.
Tan, Geoffrey C., Imbao, Jerick A., & Enriquez, Erwin P. (2013). Supercapacitor carbon electrodes from pyrolyzed glycerol. 28th Philippine Chemistry Congress, (p. v). Philippines