Biomass-based porous carbon beehive prepared in molten KOH for capacitors

ABSTRACT

Porous carbon with well-defined mesopores and macropores by simply carbonisation of biomass waste i.e. soybean straw in molten KOH at 800°C is reported herein. Benefiting from the high fluidity of high-temperature liquidus molten salt, the released gaseous products during pyrolysis of soybean straw in molten salt leads to a rigorous bubbling phenomenon, contributing to a well-defined beehive-like structure of pyrolysis-derived carbonaceous product with a high surface area up to 1615 m² g⁻¹. When evaluated as electrode material for capacitors, the biomass-derived porous carbon exhibits a high specific capacitance of 140 F g⁻¹ even at a high current density of 10 A g⁻¹ in 1 M H₂SO₄ solution. This study underlines KOH as a green and cost-affordable pore-forming thermal media for biomass waste carbonisation.

KEYWORDS:

• Molten salt carbonisation
• biomass
• porous carbon
• capacitor

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the Science & Technology Project of the General Administration of Quality Supervision, Inspection and Quarantine of China [2017IK055].