Cellulose nanofibers as effective binders for activated biochar-derived high-performance supercapacitors

Md Manik Mian; Ishimwe Marie Louise Kamana; Xingye An; Syed Comail Abbas; Md Sohel Ahommed; Zhibin He; Yonghao Ni

doi:10.1016/j.carbpol.2022.120353

Cellulose nanofibers as effective binders for activated biochar-derived high-performance supercapacitors

Carbohydr Polym. 2023 Feb 1;301(Pt B):120353. doi: 10.1016/j.carbpol.2022.120353. Epub 2022 Nov 17.

Authors

Md Manik Mian¹, Ishimwe Marie Louise Kamana¹, Xingye An², Syed Comail Abbas¹, Md Sohel Ahommed¹, Zhibin He¹, Yonghao Ni³

Affiliations

¹ Department of Chemical Engineering, University of New Brunswick, Fredericton, NB E3B 5A3, Canada.
² Department of Chemical Engineering, University of New Brunswick, Fredericton, NB E3B 5A3, Canada; Tianjin Key Laboratory of Pulp and Paper, Tianjin University of Science and Technology, No. 29, 13thStreet, TEDA, Tianjin, 300457, PR China.
³ Department of Chemical Engineering, University of New Brunswick, Fredericton, NB E3B 5A3, Canada; Department of Chemical and Biomedical Engineering, University of Maine, Orono, ME 04469, USA. Electronic address: yonghao@unb.ca.

PMID: 36446512
DOI: 10.1016/j.carbpol.2022.120353

Abstract

Traditional hydrophobic binders can limit supercapacitors' performance by impeding ion accessibility. Herein, we demonstrate the potential of plant-derived environmentally friendly Cellulose Nanofibers (CNF) as binders for biochar (BN-Ac)-based supercapacitors. The CNF binder retains BN-Ac's micropores and improves wettability, while the Polyvinylidene Fluoride (PVDF) binder fills micropores and hinders ion-conductive pathways. The as-synthesized BN-Ac/CNF exhibits a capacitance of 268.4 F g^-1 at 5 A g^-1, which is 1.4 times higher than that of BN-Ac/PVDF. In addition, the energy density improves from 4.6 to 5.7 Wh kg^-1 at 2.1 and 2.5 kW kg^-1 power, respectively, for replacing PVDF with CNF. More importantly, BN-Ac/CNF shows outstanding capacitance retention of 96.2 % after 10,000 charge/discharge cycles. The improved wettability and reduced bulk electrolyte resistance by hydrophilic CNF binders are responsible for the electrode's high capacitance. Concurrently, this study showcases a facile strategy for improving supercapacitor performance and a green application of CNF in energy devices.

Keywords: Binder; Biochar; Cellulose nanofibers; EDLCs; Supercapacitor.

MeSH terms

Cellulose
Nanofibers*
Polyvinyls

Substances

Cellulose
polyvinylidene fluoride
biochar
Polyvinyls