Polypyrrole/hexadecylpyridinium chloride-modified graphite oxide composites: Fabrication, characterization, and application in supercapacitors

• A facile method for synthesizing PPy/MGO composites by in situ polymerization.
• Observation of the markedly morphological distinction between PPy/GO and PPy/MGO.
• Excellent electrochemical performance of PPy/MGO composites.
• Excellent cycle stability and energy performance of PPy/MGO composites.

We report a facile and effective method for synthesizing polypyrrole/modified graphite oxide (PPy/MGO) composites by in situ polymerization. The graphite oxide (GO) is modified with hexadecylpyridinium chloride (CPC) and then composited with PPy. Scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) results demonstrate that PPy chains may combine with CPC molecule via π–π stacking interaction and the structures of PPy/GO and PPy/MGO composites are completely different. Cyclic voltammetry (CV), galvanostatic charge–discharge (GCD), and electrochemical impedance spectrum (EIS) tests indicate that, at the current density of 1 A g−1, the specific capacitance and energy density of PPy/MGO are 202 F g−1 and 8.49 Wh kg−1 in three-electrode systems and those are 87 F g−1 and 10 Wh kg−1 in two-electrode systems; the capacitance retention of PPy/MGO is 83.8% after 1000 cycles at a scan rate of 1 A g−1; PPy/MGO also exhibited excellent energy performance from Ragone charts. Based on these properties, the PPy/MGO composites may become a promising material for supercapacitor applications.