Synergistic effect of sulfur-doped reduced graphene oxide created via microwave-assisted synthesis for supercapacitor applications

Doping heteroatoms is an effective means of modifying the electrochemical properties of reduced graphene oxide (rGO). In this work, we propose the modification of rGO via microwave-assisted synthesis with different concentrations of sulfur at 140 degrees C for 30 min. Characterization using X-ray diffraction, Fourier-transform infrared, and Raman spectroscopy revealed successful doping with sulfur to alter the physical properties of rGO. The morphology of doped S-rGO samples exhibited wrinkling and folding of graphene sheets. Electrochemical evaluation revealed S-rGO with 0.25 M of sulfur (S-rGO-0.25) to have excellent electrochemical performance, with a specific capacitance of 237.6 F g(-1) compared to the S-rGO with 0.15 M (S-rGO-0.15) and S-rGO with 0.50 M (S-rGO-0.50) with 98.2 and 61.7 F g(-1) respectively. Furthermore, S-rGO-0.25 was validated as having an outstanding capacitance retention of 106% after 10,000 cycles signifying that it has promising potential as an electrode material for supercapacitor applications.