Activated Carbon for Supercapacitor Electrodes Produced by the Carbonation and Activation of Glucose with Potassium Nitrate

The preparation of activated carbon has long been a subject of interest for researchers aiming to develop a straightforward and environmentally friendly method. This study introduces an approach for carbonizing glucose using potassium nitrate to ignite and carbonize glucose, resulting in the production of fluffy carbon. Activated carbon suitable for supercapacitor production can be obtained through postprocessing involving calcination and pickling. An important feature of this method is that it does not require the use of a strong alkali, such as potassium hydroxide, for the activation reaction following carbonization. Based on experimental results, optimal activated carbon is produced when the proportion of potassium nitrate in the feedstock is 50%. Furthermore, activated carbon with superior physical characteristics can be utilized in the assembly of organic electrolyte supercapacitors, and their electrical properties can be analyzed. The results indicate that the supercapacitor assembled by using activated carbon with 50% potassium nitrate in the raw material demonstrates the best performance. Its cyclic voltammetry (CV) curve approximates a rectangle and exhibits an almost vertical curve at low frequencies in the Nyquist plot. Additionally, for the analysis of the galvanostatic charge–discharge behavior of the supercapacitor, the curve maintains an equilateral triangle pattern even at a current density of 5A/g. The results also show that the best supercapacitor achieves 38.41 and 153.66 F/g for capacitor-specific capacitance and electrode-specific capacitance, respectively.