Salt sealing strategy to prepare N,O-codoped porous bio-carbon derived from Ephedra Herb for supercapacitors

Herein, unique N,O-codoped porous biocarbon (PB) was prepared using Ephedra Herb (EH) as a precursor via a green and sustainable NaCl-sealing strategy and subsequent pyrolysis method. PB possesses vast microstructure, interlinked pores, and high specific surface area, which can facilitate ion adsorp...

Full description

Saved in:
Bibliographic Details
Published inNew journal of chemistry Vol. 45; no. 36; pp. 16648 - 16657
Main Authors Liu, Jing-Jiang, Yan, Zhi-Wei, Kang, Rui-Xue, Wang, Jin-Hui, Feng, Xun
Format Journal Article
LanguageEnglish
Published Cambridge Royal Society of Chemistry 28.09.2021
Subjects
Carbon
Electrochemical analysis
Electrode materials
Electrodes
Energy storage
Flux density
Herbs
Ion adsorption
Porosity
Pyrolysis
Sealing
Specific surface
Supercapacitors
Surface area
Online AccessGet full text

Cover

More Information
Summary:Herein, unique N,O-codoped porous biocarbon (PB) was prepared using Ephedra Herb (EH) as a precursor via a green and sustainable NaCl-sealing strategy and subsequent pyrolysis method. PB possesses vast microstructure, interlinked pores, and high specific surface area, which can facilitate ion adsorption and buffering to improve its properties as an electrode material. In addition, the high specific surface area, well-developed porosity, and abundant heteroatoms in EH are retained well owing to the salt-sealing approach, contributing to additional pseudocapacitance. Therefore, a typical PB sample (S 12 ), obtained from the NaCl-sealing and pyrolysis of the mixture of EH and NaCl at a mass ratio of 1 : 2, is endowed with high specific capacitance, excellent rate performance, and performance retention over long-term cycling. Most importantly, an aqueous symmetrical supercapacitor (S 12 //S 12 ) assembled with S 12 electrodes has a superior specific energy density of 11.6 W h kg −1 at a specific power density of 450.1 W kg −1 in Li 2 SO 4 electrolyte. This work confirms the utility of a NaCl-sealing strategy for designing high specific surface area biocarbon materials that are ultra-rich in micropores, and it sheds some light on the use of sustainable and low-cost synthetic carbon that is ultra-rich in micropores to meet energy-storage device requirements. The high specific surface area, vast microstructure, and large number of heteroatoms of Ephedra Herb are well retained owing to the salt-sealing method developed here.
Bibliography:10.1039/d1nj03245c
Electronic supplementary information (ESI) available: Information relating to the fabrication of the three-electrode system, the fabrication of the two-electrode supercapacitor, material characterization, and electrochemical measurements; Fig. S1-S9. See DOI
ISSN:1144-0546
1369-9261
DOI:10.1039/d1nj03245c