Effect of nitrogen doping on the electrochemical performance of resorcinol-formaldehyde based carbon aerogels as electrode material for supercapacitor applications. (15th April 2019)

• Record Type: Journal Article
• Authors: Mirzaeian, Mojtaba; Abbas, Qaisar; Gibson, Des; Mazur, Michal
• Is Part Of: Energy. Volume 173(2019)
• Page Start: 809
• Page End: 819
• Publication Date: 2019-04-15
• Subjects: Nitrogen doped carbon aerogels -- Porous structure -- Functional groups -- Electrode/electrolyte interface -- Electrochemical performance; Power resources -- Periodicals; Power (Mechanics) -- Periodicals; Energy consumption -- Periodicals; 333.7905
• DOI: 10.1016/j.energy.2019.02.108
• Languages: English
• ISSNs: 0360-5442

Abstract

Abstract: Nitrogen doped resorcinol/formaldehyde carbon aerogels with controlled nitrogen content are synthesized by controlling the resorcinol/melamine molar ratio (R/M) during the synthesis of aerogel precursors. The carbons were used as electrode materials in an electrochemical capacitor using 6 M KOH solution as electrolyte. All samples exhibited amorphous structure with low degree of graphitization. The maximum specific capacitance of 208 Fg -1 was observed after doping of the carbon with nitrogen at R/M = 80. Drop in solution and charge transfer resistances from 0.57Ω to 0.15Ω and 0.05Ω–0.04Ω was also observed respectively, with the drop in contact angles from 123° to 103° for the carbon doped with nitrogen at R/M = 80. BET results showed that the pore volume and surface area of carbon increase after N-doping, with a BET surface area of 841 m 2 g −1 at R/M = 80. This R/M ratio is an optimum ratio at which incorporation of nitrogen into the carbon matrix improves the capacitive performance of cell as a result of improved porosity/wettability/conductivity/active sites of the electrode. Doping at higher nitrogen concentrations (R/M < 80) decreased the specific capacitance of the cell significantly due to decreased conductivity of carbon and suppression of the hopping rate of dopant. Graphical abstract: Image 1078 Highlights: Nitrogen doped resorcinol/formaldehyde carbon aerogels with controlled nitrogen content are synthesized. The contact angle of carbon and 6 M KOH solution dropped significantly from 123° to 103° after nitrogen doping. The best specific capacitance of 208 Fg -1 is obtained for the carbon doped with nitrogen at an R/M ratio of 80. The solution resistance dropped significantly from 0.57Ω to 0.15Ω after N- doping at an R/M ratio of 80. R/M ratio of 80 is the optimum R/M ratio at which nitrogen doping results in superior performance of the cell.