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Nano Research 2020, 13(6): 1604-1613 https://doi.org/10.1007/s12274-020-2778-9
Research Article | Issue | Published: 14 May 2020

Rationally exfoliating chitin into 2D hierarchical porous carbon nanosheets for high-rate energy storage

Show Author's Information Lingfeng Gao1,§,  Guoqun Zhang2,§,  Jie Cai1,  Liang Huang2( ),  Jun Zhou2,  Lina Zhang1( )
College of Chemistry and Molecular Science, Hubei Engineering Center of Natural Polymer-based Medical Materials, Wuhan University, Wuhan 430072, China
Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, China

§ Lingfeng Gao and Guoqun Zhang contributed equally to this work.

Keywords:
energy storage, mass production, two-dimensional carbons materials, hierarchical porosity
Topics:
CarbonConductive filmsElectrochemical electrodesElectrolytesEnergy storageLithium compoundsNanosheetsPorosityPorous materialsPotassium hydroxideSemiconductor dopingSupercapacitor
Cite this article:
Gao L, Zhang G, Cai J, et al. Rationally exfoliating chitin into 2D hierarchical porous carbon nanosheets for high-rate energy storage. Nano Research, 2020, 13(6): 1604-1613. https://doi.org/10.1007/s12274-020-2778-9
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Abstract Full text Electronic supplementary material About this article

Two-dimensional (2D) carbon nanomaterials with hierarchical porous structure and heteroatoms doping are highly desirable in the fields of energy storage because of their rich active surface and open ion diffusion channels. However, the scalable preparation of carbon materials simultaneously possessing ultrathin 2D feature and hierarchical pores remains a considerable challenge. Herein, a facile one-step method to massively fabricate 2D porous chitin nanosheets (coded as PCNs) via a phytic acid assisted top-down exfoliation of bulk chitin under hydrothermal treatment was presented. Subsequently, 2D carbon nanosheets with extra-thin thickness (3.6 nm), well-defined hierarchical porosity, high specific surface area (855 m2·g-1), as well as abundant self-doped heteroatoms (N, O, P) were fabricated by carbonizing the PCNs, and was named as HPCNs. The as-obtained HPCNs demonstrated remarkable electrochemical performance as electrode material for supercapacitors. The symmetric supercapacitors (SSCs) based on HPCNs exhibited a high specific capacitance of 79 F·g-1 (316 F·g-1 for single electrode) in 6 M KOH aqueous electrolyte solution, as well as a remarkable energy density of 23.8 W·h·kg-1 by using 1 M Li2SO4 as electrolyte. It is also demonstrated that HPCNs/PCNs hybrid dispersions can be used as inks to fabricate conductive films and energy devices with high strength and superior flexibility. This work paves a new avenue for the economical and large-scale synthesis of 2D hierarchically porous carbon materials for energy storage related applications.


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About this article

Rationally exfoliating chitin into 2D hierarchical porous carbon nanosheets for high-rate energy storage

Show Author's information Lingfeng Gao1,§, Guoqun Zhang2,§, Jie Cai1, Liang Huang2( ), Jun Zhou2, Lina Zhang1( )
College of Chemistry and Molecular Science, Hubei Engineering Center of Natural Polymer-based Medical Materials, Wuhan University, Wuhan 430072, China
Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, China

§ Lingfeng Gao and Guoqun Zhang contributed equally to this work.

Abstract

Two-dimensional (2D) carbon nanomaterials with hierarchical porous structure and heteroatoms doping are highly desirable in the fields of energy storage because of their rich active surface and open ion diffusion channels. However, the scalable preparation of carbon materials simultaneously possessing ultrathin 2D feature and hierarchical pores remains a considerable challenge. Herein, a facile one-step method to massively fabricate 2D porous chitin nanosheets (coded as PCNs) via a phytic acid assisted top-down exfoliation of bulk chitin under hydrothermal treatment was presented. Subsequently, 2D carbon nanosheets with extra-thin thickness (3.6 nm), well-defined hierarchical porosity, high specific surface area (855 m2·g-1), as well as abundant self-doped heteroatoms (N, O, P) were fabricated by carbonizing the PCNs, and was named as HPCNs. The as-obtained HPCNs demonstrated remarkable electrochemical performance as electrode material for supercapacitors. The symmetric supercapacitors (SSCs) based on HPCNs exhibited a high specific capacitance of 79 F·g-1 (316 F·g-1 for single electrode) in 6 M KOH aqueous electrolyte solution, as well as a remarkable energy density of 23.8 W·h·kg-1 by using 1 M Li2SO4 as electrolyte. It is also demonstrated that HPCNs/PCNs hybrid dispersions can be used as inks to fabricate conductive films and energy devices with high strength and superior flexibility. This work paves a new avenue for the economical and large-scale synthesis of 2D hierarchically porous carbon materials for energy storage related applications.

Keywords: energy storage, mass production, two-dimensional carbons materials, hierarchical porosity

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Publication history
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Acknowledgements

Publication history

Received: 10 February 2020
Revised: 20 March 2020
Accepted: 23 March 2020
Published: 14 May 2020
Issue date: June 2020

Copyright

© Tsinghua University Press and Springer-Verlag GmbH Germany, part of Springer Nature 2020

Acknowledgements

This work was supported by the Major Program of National Natural Science Foundation of China (No. 21334005), and the Major International (Regional) Joint Research Project (No. 21620102004). The authors gratefully acknowledge the Analytical and Testing Center of WHU for allowing us to use its facilities.

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