A melamine-assisted chemical blowing synthesis of N-doped activated carbon sheets for supercapacitor application

• N-doped activated carbon sheets (NACSs) are prepared by a chemical blowing method.
• This synthetic method is novel and convenient than other traditional routes.
• NACS material possesses hierarchical porous structure and high nitrogen content.
• It shows a high specific capacitance of 312 F g−1 and good rate performance.
• The energy density of NACS supercapacitor reaches 20.2 Wh kg−1 at 448 W kg−1.

N-doped activated carbon sheets (NACS) have been successfully synthesized using glucose as carbon source via melamine-assisted chemical blowing and sequent KOH-activation method. The obtained carbon material possesses a sheet-like morphology with ultrathin thickness, hierarchical micro/mesoporous structure, high specific surface area (up to 1997.5 m2 g−1) and high pore volume (0.94 cm3 g−1). Besides, NACS material with a nitrogen content of 3.06 wt% presents a maximum specific capacitance of 312 F g−1 at a current density of 0.5 A g−1 in 6 M KOH aqueous electrolyte due to the cocontribution of double layer capacitance and pseudocapacitance. It also displays good rate performance (246 F g−1 at 30 A g−1) and cycle stability (∼91.3% retention after 4000 galvanostatic charge-discharge cycles). The assembled NACS-based symmetric capacitor exhibits a maximum energy density of 20.2 Wh kg−1 at a power density of 448 W kg−1 within a voltage range of 0–1.8 V in 0.5 M Na2SO4 aqueous electrolyte. Thus, the unique porous sheet structure and nitrogen-doping characteristic endue the electrode material a potential application for high-performance supercapacitors.

N-doped activated carbon sheets have been successfully synthesized by a melamine-assisted chemical blowing route, which exhibit high specific capacitance, excellent rate performance and high energy/power densities.Figure optionsDownload as PowerPoint slide