Doped Graphitic Carbon Nitride: An Efficient Supercapacitor Material

Synthesis of graphitic carbon nitride (GCN) has been done by simply solid-state heating of urea at a moderate temperature of 550 °C. The synthesized GCN was further doped by transition metal like nickel using nickel nitrate as precursor. The X-ray diffraction shows that after doping the sample loses its crystallinity considerably, whereas FESEM micrograph shows after doping the chips-like structure of pure GCN get profound elongation around a specific direction. XPS spectrum confirms the doping of the sample with profound 2p peak of nickel. When FTIR spectra were taken it was seen that the spectra contain profound FTIR pattern that is characteristics of pure GCN, whereas after doping the spectra also shows profound shifting from its initial pattern. All these collectively suggest that doping causes considerable changes in internal crystal structure of GCN. Both the pure and doped GCN shows promises as charge storage material when cyclic voltammetry study was performed with two different scan rates. However, the doped sample shows value of specific capacitance as high as 90 F/g much higher compared to that of the pure sample. The charge-discharge characteristic of the doped sample also shows a marked change in pattern compared to the pure one. The EIS spectra of both the samples show a capacitive nature showing the promises of the system toward supercapacitor applications.