Preparing of Carbon Nanodots from Binchotan Carbon by Electrochemically Sonification and Dialysis

Abstract

This paper reports the research of preparing an aqueous solution of binchotan carbon electrochemically and followed by its purification through sonification and dialysis. Binchotan rod and platinum plate were used as anode and cathode. The electrodes were placed on both sides of beaker glass that contained 200 ml of 14 M sulphuric acid, oxalic acid and phosphoric acid solutions as electrolytes, respectively. The potential between anode and cathode was 14 V. The solution was moved from beaker glass after 24 hours, filtered to produce a solid product for further examinations. The solid was washed with distilled water until pH 7, dried in 100 °C ovens. Two types of materials were examined, i.e. the product before and after the purification. The solid was then characterized by its morphology, crystallography, and surface functional groups by SEM, XRD, and FT-IR. The morphology of the binchotan after running the electro-oxidation process generally were aggregates and dots. Both shapes were reduced in size after purification. The diffractogram showed a significant change at 2θ=14°-44° meaning that the purification process changes the crystallography of carbon. The FTIR showed the presence of a functional group of aromatic, carboxylic, alkene, and alcohol on the surface of the carbon.