Comparison between atmospheric-pressure-plasma-jet-processed and furnace-calcined rGO-MnOx nanocomposite electrodes for gel-electrolyte supercapacitors
Jheng-Yun Lai, Cheng‐Che Hsu, Jian‐Zhang Chen
Abstract
Reduced graphene oxide (rGO)-Mn(NO3)2·4H2O pastes were screen-printed on a carbon cloth substrate and then calcined using a nitrogen atmospheric-pressure-plasma-jet (APPJ) and/or tube furnace to convert it into rGO-MnOx. The rGO-MnOx electrodes were then used in a PVA/H2SO4 gel-electrolyte supercapacitor (SC). The SCs were characterized by cycle voltammetry (CV) and galvanostatic charging/discharging (GCD). The results reveal better performance of the APPJ-processed SCs in comparison with furnace-processed ones under the same processing temperature, possibly owing to the synergetic effect of heat and reactive nitrogen plasma species. The rGO-MnOx SC is also superior to the rGO-SnOx SC reported in our previous study processed under similar APPJ processing. The rGO-MnOx SC processed by APPJ at 620 °C for 8 min exhibits the best areal capacitance of 57.01 mF/cm2 as evaluated by GCD with a capacitance retention rate of 84.41% after a 10,000-cycle CV test.