Creating ultrahigh surface area functional carbon from biomass for high performance supercapacitor and facile removal of emerging pollutants

Recent decade has seen enormous interest in developing cost effective, simple and greener method of utilizing naturally abundant and renewable resources to mitigate the concerns relating contaminated water sources and store green energy. Carbon materials derived from biomass have drawn great attention because of their abundance, easy processability, tunable surface properties and relatively low cost. Present work demonstrates the conversion of abundant and toxic weed, Parthenium hysterophorous to porosity enriched ultrahigh surface area activated carbon with a surface area of 4014 m(2)/g and a large porous volume of 2.0419 cm(3)/g. The optimized carbon materials before and after activation showed crumpled sheet-like morphology with oxygenated functionalities (C/O = 6.352) as confirmed by different analytical tools. Electrochemical studies revealed that the supercapacitor device assembled using the as prepared carbon material manifest an significant specific capacitance of 270 F/g, exhibiting excellent capacity retention of 98.5 % even after 30,000 cycles at an increased current density of 10 A/g. Further, a membrane was prepared using functional carbon material for the removal of different organic pollutants such as dyes (methylene blue, malachite green, eriochrome black T, congo red) and pharmaceutical wastes (paracetamol, cipmfloxacin) from aqueous media. The functional carbon based membrane showed high rejection for cationic dyes (93-99.5%) comparing to anionic dyes (46-67%) with a flux rate in the range of 820-840 Lm(-2)h(-1) and maximum adsorption capacity of 194 mg/g for methylene blue dye. Similarly, for cationic pharmaceutical wastes higher rejection (90-95%) was achieved with an average flux of 830 Lm(-2)h(-1). Moreover, recyclability studies of the membrane affirmed a retention of 91.6% rejection of methylene blue even after 10 consecutive cycles without compromising the flux rate which confirmed the suitability of the toxic weed derived functional carbon as a sustainable alternative for water purification in a continuous flow method.