Title: A Flexible, Redox-Active, Aqueous Electrolyte-Based Asymmetric Supercapacitor with High Energy Density Based on Keratin-Derived Renewable Carbon

Abstract

Abstract This work exploits the advantage of asymmetric configuration over symmetric supercapacitor in designing high energy density flexible devices from two active electrode materials–keratin‐based renewable‐resource hierarchically porous carbon and hydrous ruthenium oxide (RuO ₂ ). The asymmetric device exhibits significantly high capacitance. Conventional estimation of energy storage parameters, however, cannot be applied for devices with a Faradaic energy storage contribution via redox charge transfer mechanism. Therefore, this work applies a precise measurement of pseudocapacitance contribution at various scan rates to correct the device data that reveals effective capacitance of 120 F g ⁻¹ with the energy density of 37 W h kg ⁻¹ at 776 W kg ⁻¹ . It also retains excellent rate capability, >74% at high current density 25 A g ⁻¹ . The charge storage activity and device stability can be further enhanced by introducing redox‐active electrolytes that improve specific capacitance, but the rate capabilities deteriorate at high current densities. Further, the principle of asymmetric electrode design is applied to fabricate a bending‐tolerant, flexible device by depositing active electrode material on wire‐shaped current collector followed by coupling those separated with polyvinyl alcohol gel containing redox electrolyte; it yields 36.8 mF cm ⁻¹ specific capacitance at a 0.2 mA cm ⁻¹more » current density.« less

Authors:

Sinha, Prerna  ^[1];

• Search DOE PAGES for author "Sinha, Prerna"
• Search DOE PAGES for ORCID "0000-0002-6001-5250"

Kar, Kamal K.  ^[1];

• Search DOE PAGES for author "Kar, Kamal K."
• Search DOE PAGES for ORCID "0000-0002-6449-3399"

Naskar, Amit K.  ^[2]

• Search DOE PAGES for author "Naskar, Amit K."
• Search DOE PAGES for ORCID "0000-0002-1094-0325"

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+ Show Author Affiliations

1. Indian Inst. of Technology (IIT), Kanpur (India)
2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Publication Date:

Tue Jun 28 00:00:00 EDT 2022

Research Org.:

Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)

Sponsoring Org.:

Science and Engineering Research Board; USDOE Laboratory Directed Research and Development (LDRD) Program

OSTI Identifier:

1883867

Alternate Identifier(s):

OSTI ID: 1897946

Grant/Contract Number:  

AC05-00OR22725; DE‐AC05‐00OR22725

Resource Type:

Accepted Manuscript

Journal Name:

Advanced Materials Technologies

Additional Journal Information:

Journal Volume: 7; Journal Issue: 11; Journal ID: ISSN 2365-709X

Publisher:

Wiley

Country of Publication:

United States

Language:

English

Subject:

36 MATERIALS SCIENCE; asymmetric supercapacitors; energy density; hierarchical porous carbon; hydrous RuO2; redox-active electrolytes