A simple and green approach to develop porous carbons from biomass lignin for advanced asymmetric supercapacitors

• Published in: Colloids and surfaces. A, Physicochemical and engineering aspects Vol. 652; p. 129785
• Main Authors: Kim, Da-Young, Ma, Cho-Hi, Jang, Yeonju, Radhakrishnan, Sivaprakasam, Ko, Tae Hoon, Kim, Byoung-Suhk
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 05.11.2022
• Subjects: Activation; Hydrothermal; Lignin; N- and S-doped carbon; Porous carbon; Lignin; Porous carbon; Activation; N- and S-doped carbon; Hydrothermal
• ISSN: 0927-7757
• DOI: 10.1016/j.colsurfa.2022.129785

We present the biomass lignin-derived porous carbons (LPCs) prepared by a simple and environmentally friend hydrothermal treatment in presence of H2SO4 catalysts and then KOH activation to boost specific surface area and the corresponding electrochemical performance. The resultant LPC products were further subjected to simultaneous heteroatom N-doping during activation process, resulting in the activated N-doped LPCs (N-LPCs) for supercapacitors. The morphologies, crystal structures and textural properties of the obtained N-LPCs were studied by scanning electron microscopy, X-ray diffraction and nitrogen sorption isotherms. The N-LPCs exhibited highly porous microstructure (BET surface area: 1990.49 m2 g−1) and excellent capacitance value of 301 F g−1 at 1 A g−1, good rate capacitance of 70.9% at various densities from 1 A g−1 to 20 A g−1, and outstanding cycling performance of 91.3% over 20,000 charge-discharge cycles. Further, full-cell supercapacitor device assembled using the N-LPCs (as anode) and nickel cobalt layered double hydroxide (NiCo-LDH, as cathode) demonstrated an excellent specific capacitance (250 F g−1 at 1 A g−1), high retention (60% at 15 A g−1) and remarkable energy density of 78 Wh kg−1. [Display omitted] •A highly porous carbon prepared from inexpensive lignin source.•The porous carbon (PC) has a high surface area (1990.49 m2 g−1).•The asymmetric supercapacitor cell is fabricated using PC as anode.•The fabricated cell shows an excellent energy density of 78 Wh kg−1.