Unveiled Supercapacitive Performance of Se-doped Graphene Nanoarchitectonics Prepared via Supercritical Fluid Technique

Doping of graphene with variety of heteroatoms is presently focused for electrochemical supercapacitor applications because it functions as a hybrid supercapacitor. Herewith, we report the fabrication of Se-doped graphene with selenium dioxide using a supercritical fluid technique. Both the existence as well as the quantity of Se-doping in graphene are established using XPS and EDAX techniques. The Se-doped graphene derived from the weight ratio of selenium dioxide and graphene oxide of 1 : 3 resulted in an enriched gravimetric capacitance achieving 581 F g(-1) (1 M H2SO4). The specific capacity of the optimised Se-doped graphene based symmetric supercapacitor in 0.01 M solution of ammonium metavanadate in 1 M H2SO4 solution is found to be 420 C g(-1) and attained an improved capacitance retention of 85% over 50000 cycles along with 94% coulombic efficiency. The energy density of the Se-doped graphene symmetric supercapacitor is found to be 23.33 Wh kg(-1) in 0.01 M solution of ammonium metavanadate in 1 M H2SO4 solution.

Automated summary

In this study, Se-doped graphene was synthesized using supercritical fluid technique and characterized by XPS and EDAX. The Se-doped graphene exhibited a gravimetric capacitance of 581 F g(-1) in 1 M H2SO4 solution and a specific capacitance of 420 C g(-1) in 0.01 M ammonium metavanadate solution in 1 M H2SO4. The Se-doped graphene symmetric supercapacitor showed an improved capacitance retention of 85% over 50000 cycles and a coulombic efficiency of 94%. The energy density of the Se-doped graphene symmetric supercapacitor reached 23.33 Wh kg(-1) in 0.01 M ammonium metavanadate solution in 1 M H2SO4 solution.