High-performance pseudo-capacitance supercapacitor with highly mesoporous fluorine doped polymeric carbon nitride nanosheets as electrode material

Abstract

In this study, graphitic carbon nitride (GCN) material obtained from urea was hydrothermally doped with fluorine atoms (F-doped GCN). The resulting F-doped GCN material was designed as an electrode material for supercapacitors. Characterization of these samples was carried out by XRD, EDS, SEM, nitrogen adsorption and FTIR analyses. EDS and FTIR analyses confirmed the doping of fluorine atoms onto GCN. Nitrogen adsorption analyses supported the formation of a significant mesoporous structure with fluoride doping on GCN. The specific capacitance values of the GCN and F-doped GCN supercapacitors were calculated as 39.75 F/g and 305.72 F/g at a frequency of 0.01 Hz. A significant increase of about 7-fold in capacitance value was obtained by fluorine doping on GCN. Cycling trials of the F-doped GCN supercapacitor for up to 1000 cycles at a current density of 0.4 A/g maintain an efficiency of 86.72 %. For the supercapacitor designed from F-doped GCN material, the maximum energy density and power density were calculated as 4.26 Wh/kg and 1792 Wh/kg, respectively.