Hierarchical porous carbon monolith derived from lignin for high areal capacitance supercapacitors

• Published in: Microporous and mesoporous materials 2020-05, Vol.297, p.109960, Article 109960
• Main Authors: Li, Hui, Zhao, Yuhui, Liu, Siqi, Li, Pengcheng, Yuan, Du, He, Chaobin
• Format: Article
• Language: English
• Subjects: Areal capacitance; Hierarchical porous carbon; Lignin; Supercapacitors
• ISSN: 1387-1811; 1873-3093
• DOI: 10.1016/j.micromeso.2019.109960

Hierarchical porous carbon with high areal energy density in supercapacitor has attracted extensive attention with increasing demand for compact and portable devices. Lignin based porous carbon monolith was fabricated via dual templates (P123 and silica nanoparticles) and carbonization procedure, where hierarchical porous structure with tuneable mesopore sizes and distributions could be modulated via incorporation of silica nanoparticles with size of 200 nm, 100 nm, and 7 nm, respectively. Due to higher surface area and optimized porous structure which facilitate fast ion diffusion, carbon monolith fabricated from silica nanoparticle of 7 nm exhibited superior electrochemical performance, which reached a high areal capacitance of 2.7 F cm−2 and excellent volumetric capacitance of 104.5 F cm−3 with mass loading of 13.6 mg cm−2 in 6 M KOH aqueous solution. Moreover, the symmetric cell assembled with this carbon electrode gave rise to a large amount of energy (131 μWh cm−2) at high power densities (1368 μW cm−2) and excellent cycle stability of 92.9% after 10 000 cycles, facilitating implementation of lignin-derived materials in commercial energy storage products. [Display omitted] •Lignin derived hierarchical porous carbon monolith was fabricated by dual templates.•The porous structure can be tuned by the size and amount of silica nanoparticles.•High capacitance performance can be realized by optimizing porous structure.•2.7 F cm−2, 104.5 F cm−3, and 200.2 F g−1 were achieved at 0.1 A g−1.