Tauno Tooming

Carbon materials for supercapacitor application by hydrothermal carbonization of D-glucose

Hydrothermal carbonization (HTC) of 1 M D-glucose solution was carried out in a stainless steel autoclave, which was introduced into a tube furnace and maintained at the temperature 260 °C for 24 hours for HTC reaction. Obtained carbonaceous materials were pyrolyzed and activated using carbon dioxide to fine-tune the porosity of HTC carbons. Raman spectroscopy and high resolution transmission electron microscopy data revealed that synthesised carbon materials were mainly amorphous. Scanning electron microscopy studies demonstrated that carbon materials were consisted of micrometer scale mainly spherically shaped particles maintaining their shape and structure throughout pyrolysis and activation processes. Based on the low-temperature N2 sorption experiments the specific surface areas up to 1540 m2 g−1 were measured for differently activated HTC. Various electrochemical methods were used to study influence of carbon materials physical characteristics on the supercapacitor electrochemical performance based on HTC carbon electrodes in 1 M (C2H5)3CH3NBF4 solution in acetonitrile.