Incorporating Conducting Polypyrrole into a Polyimide COF for Carbon‐Free Ultra‐High Energy Supercapacitor
Abstract
Redox‐active covalent organic frameworks (COFs) store charges but possess inadequate electronic conductivity. Their capacitive action works by storing H+ ions in an acidic electrolyte and is typically confined to a small voltage window (0–1 V). Increasing this window means higher energy and power density, but this risks COF stability. Advantageously, COF's large pores allow the storage of polarizable bulky ions under a wider voltage thus reaching higher energy density. Here, a COF–electrode–electrolyte system operating at a high voltage regime without any conducting carbon or redox active oxides is presented. Conducting polypyrrole (Ppy) chains are synthesized within a polyimide COF to gain electronic conductivity (≈10 000‐fold). A carbon‐free quasi‐solid‐state capacitor assembled using this composite showcases high pseudo‐capacitance (358 mF cm−2@1 mA cm−2) in an aqueous gel electrolyte. The synergy among the redox‐active polyimide COF, polypyrrole and organic electrolytes allows a wide‐voltage window (0–2.5 V) leading to high energy (145 μWh cm−2) and power densities (4509 μW cm−2). Amalgamating the polyimide‐COF and the polypyrrole as one material minimizes the charge and mass transport resistances. Computation and experiments reveal that even a partial translation of the modules/monomers intrinsic electronics to the COF imparts excellent electrochemical activity. The findings unveil COF‐confined polymers as carbon‐free energy storage materials.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jul 22, 2022
- Source ID
- 10.1002/aenm.202200754
Entities
People
- Chathakudath Prabhakaran Vinod
- Chitvan Jain
- Deepak Rase
- En Xia Zhang
- Leonid Shupletsov
- Pragalbh Shekhar
- Ramanathan Vaidhyanathan
- Sattwick Haldar
- Stefan Kaskel
Organizations
- Air Force Office of Scientific Research
- California Department of Fish and Wildlife
- Department of Science and Innovation
- Indian Institutes of Science Education and Research
- Science and Engineering Research Board
- Technische Universität Dresden