Asphaltene-derived nanoporous carbon materials for CO2 capture and supercapacitors

• Nanoporous carbons (1500–2000 m 2 /g) are synthesized from asphaltenes via thermo-chemical activation. • N-doping enhanced pseudocapacitance via Faradaic redox and ion diffusion (130–180 F/g). • Dynamic CO 2 breakthrough (15 %) yields 0.445 mmol/g uptake; L MTZ ∼ 1.6–1.8 cm shows fast capture. • Static profile shows CO 2 capacity up to 9.7 mmol/g (10 bar); ΔH ≈ –25 kJ/mol confirms physisorption. • N-doped microporous carbon from waste asphaltenes is promising for energy and CO 2 capture systems. Nanoporous carbon materials were synthesized from asphaltenes using a thermo-chemical treatment under an inert atmosphere and in-situ KOH activation. N-doping was also employed in certain samples to reveal the impact of nitrogen on the properties of materials. The synthesized materials were fully characterized to disclose their textural properties, structural parameters, surface functional groups, elemental compositions, and morphologies. Textural property analysis revealed a remarkable increase in surface areas after alkaline treatment (∼1500–2000 m 2 /g), which was mainly ascribed to the formation of micro- and mesopores. The measurements of structural parameters endorse and complement the findings on textural properties. The asphaltene-derived porous carbons have been employed in energy storage and carbon capture applications. The materials exhibit specific capacitances ranging from 130 to 180 F/g at 0.2 A/g in a 3 M KOH. These results suggest that nitrogen doping significantly enhances the pseudocapacitive behavior of the electroactive materials by promoting Faradaic redox reactions and improving ion diffusion and adsorption rates. Asphaltene-derived porous carbons also exhibit notable CO 2 adsorption capacities of 3–4 mmol/g at 25 °C and 1 bar. Also, breakthrough experiments confirm that the N-doped material exhibits remarkable stability, reusability, and increased surface basicity, achieving an impressive CO 2 uptake of 0.446 mmol/g. These results highlight the potential of asphaltene-based porous carbons as efficient materials for carbon capture and energy storage applications.