Nitrogen-doped banana peel–derived porous carbon foam (N-BPPCF) successfully prepared from banana peels is used as a binder-free electrode for supercapacitors. The N-BPPCF exhibits superior performance including high specific surface areas of 1357.6 m²/g, large pore volume of 0.77 cm³/g, suitable mesopore size distributions around 3.9 nm, and super hydrophilicity with nitrogen-containing functional groups. It can easily be brought into contact with an electrolyte to facilitate electron and ion diffusion. A comparative analysis on the electrochemical properties of BPPCF electrodes is also conducted under similar conditions. The N-BPPCF electrode offers high specific capacitance of 185.8 F/g at 5 mV/s and 210.6 F/g at 0.5 A/g in 6 M KOH aqueous electrolyte versus 125.5 F/g at 5 mV/s and 173.1 F/g at 0.5 A/g for the BPPCF electrode. The results indicate that the N-BPPCF is a binder-free electrode that can be used for high performance supercapacitors.

In this study, we report high catalytic activity for acetylene hydrochlorination by post-treatment of active carbon (AC) with polyaniline (PANI) followed by pyrolyzation at high temperature. The presence of PANI species in N-doped AC can be proven by transmission electron microscopy and X-ray photoelectron spectra. The N-doped AC catalyst with PANI had significantly improved catalytic activity and stability. Results demonstrated that the order of the nitrogen species' role in acetylene hydrochlorination is as follows: pyrrolic N > graphitic N > pyridinic N. It is a green, sustainable process for the polyvinyl chloride industry as a metal-free substitute for toxic HgCl₂ because of its low cost, environmental stability, and excellent catalytic performance.