Roles of Graphene Oxide in Hydrothermal Carbonization and Microwave Irradiation of Distiller’s Dried Grains with Solubles To Produce Supercapacitor Electrodes

In this paper, we developed a facile, energy-efficient process for producing highly graphitized activated carbon (AC) using wet distiller's dried grains with solubles (DDGS) as the feedstock. The three-step process included hydrothermal carbonization (HTC), KOH activation, and a short burst of direct microwave irradiation. We found that the presence of a small amount of graphene oxide (GO) in DDGS could significantly change the morphology of the produced carbon (from spherical particles to flakes) and increase the degree of carbonization and graphitization of the biomass. The AC produced with and without GO was made into supercapacitor electrodes, and their electrochemical properties were compared. This study proves that GO-assisted HTC and direct microwave irradiation is an effective method for biomass carbonization, and the AC produced using this method is a promising electrode material for supercapacitors.