Bendable and flexible supercapacitor based on polypyrrole-coated bacterial cellulose core-shell composite network. (18th May 2016)

• Record Type: Journal Article
• Authors: Wang, Fan; Kim, Hyun-Jun; Park, Sukho; Kee, Chang-Doo; Kim, Seong-Jun; Oh, Il-Kwon
• Is Part Of: Composites science and technology. Volume 128(2016)
• Page Start: 33
• Page End: 40
• Publication Date: 2016-05-18
• Subjects: Functional composites -- Layered structure -- Nanocomposites -- Electrical properties; Composite materials -- Periodicals; Composite materials; Fibrous composites; Periodicals; 620.118
• DOI: 10.1016/j.compscitech.2016.03.012
• Languages: English
• ISSNs: 0266-3538

Abstract

Abstract: We report a bendable and flexible supercapacitor based on polypyrrole-coated core-shell bacterial cellulose composite networks. As an initial step, gel-type bacterial cellulose was transformed into individually ultrathin bacterial cellulose nanofibers (TOBC) with diameters of 3–5 nm, by using 2, 2, 6, 6-tetramethylpylperidine-l-oxyl radical (TEMPO)-mediated oxidation and successive mild disintegration in water. And, PPy-TOBC core-shell nanofiber network electrodes were synthesized in situ by oxidative polymerization of pyrrole with iron (III) chloride on the TOBC nanofibers in aqueous medium. The PPy-TOBC core-shell nanofiber network electrode exhibited a high porosity (101 m 2 /g) and high conductivity (∼6.63 S/cm) due to the homogenous coating of PPy nanoparticles on the TOBC nanofiber network. The as-prepared PPy-TOBC supercapacitor cell, fabricated with PVDF-EMIMBF4 (1-Ethyl-3-methylimidazolium tetrafluoroborate) polymer electrolyte, showed a specific capacitance of 153 F/g and energy density of 21.22 Wh/kg at the current density of 0.2 A/g. Moreover, the PPy-TOBC supercapacitor exhibited an exceptionally good cyclic stability with ∼93% capacitance retention after 100 cycles; it also showed good bending stability due to the mechanical failure tolerance of the nanofiber-networked electrodes. The present approach is a versatile, inexpensive, and promising way to develop the cellulose-based nanofiber network electrodes for practical energy storage applications.