A new route of magnetic biochar based polyaniline composites for supercapacitor electrode materials

•Magnetic biochar (MB) was successfully produced by employing durian's rind as the raw material.•The vacuum condition in an electrical muffle furnace during the pyrolysis was described.•In-situ polymerization process was carried out to generate the novel MB - polyaniline (PANI) composite.•The MB demonstrated a high surface area value of 835 m2/g.•The MB - PANI composite exhibited a highest specific capacitance of 615 F/g at 10 mV/s and energy density of 76.88 Wh/kg.

In this paper, abundantly available durian's rind was opted as raw material to synthesize magnetic biochar in the presence of three different metallic salts by employing a novel vacuum condition in an electrical muffle furnace. Magnetic biochar was successfully produced with a maximum BET surface area value of 835 m2/g at the pyrolysis temperature and time of 800 °C and 25 min. This magnetic biochar was successfully employed to support and disperse polyaniline (PANI) particles for the application as supercapacitor electrode materials. The produced magnetic biochar - PANI composite exhibited an enhanced specific capacitance compared to the pure PANI and magnetic biochar. The highest specific capacitance of 615 F/g at 10 mV/s and energy density of 76.88 Wh/kg were demonstrated by the MBCA composite, which is considered favorably high compared to the existing PANI coated carbon composites. This magnetic biochar - PANI composites exhibits a good potential for future supercapacitor applications.