Black-to-transparent electrochromic capacitive windows based on conjugated polymers

Minsu Han, Cheol Hyun Cho, Hwandong Jang, Eunkyoung Kim

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8 Citations (Scopus)


A black-to-transparent electrochromic capacitive window (BTECCW) is explored through the combination of a dual electrochromic polymer (ECP) and a capacitive polymer layer. A black-colored polymer (PEB1) is obtained using 3,3-bis((2-ethylhexyloxy)methyl)-3,4-dihydro-2H-thieno[3,4-b][1,4]dioxepine and 4,7-dibromo-2,1,3-benzothiadiazole monomer, through a concerted metalation-deprotonation pathway. A high color contrast ECP layer is obtained by coating a poly(3,3-bis(bromomethyl)-3,4-dihydro-2H-thieno[3,4-b][1,4]dioxepine) (PR-Br) layer on ITO glass and then coating PEB1 over PR-Br to form a dual ECP layer. A porous and ordered polyaniline film is grown from aniline interfaced-graphene flakes, to provide a capacitive layer with a high surface area (31.8 m2g−1) and electrical conductivity (25 S cm−1). The combination of the above ECP and capacitive layer affords a highly transparent (>75%) and a large color contrast (65%) BTECCW, which shows a large energy density (26.9 W h kg−1) and a power density (23.9 kW kg−1). The redox energy of the BTECCW is stored and used to fuel an electronic clock and R-LED. These results confirm that BTECCWs can function as a battery for energy storage while being a smart window that can control the blocking and transmission of visible light. A 10 × 10 cm2size BTECCW is demonstrated, to feature the scalability of the electrochromic capacitive window.

Original languageEnglish
Pages (from-to)16016-16027
Number of pages12
JournalJournal of Materials Chemistry A
Issue number29
Publication statusPublished - 2021 Aug 7

Bibliographical note

Funding Information:
This research was supported by a National Research Foundation of Korea (NRF) grant funded by Korean government (Ministry of Science, ICT & Future Planning, MSIP) through the Global Research Lab (NRF-2016K1A1A2912753) and Creative Materials Discovery Program (NRF-2018M3D1A1058918).

Publisher Copyright:
© The Royal Society of Chemistry 2021.

All Science Journal Classification (ASJC) codes

  • Chemistry(all)
  • Renewable Energy, Sustainability and the Environment
  • Materials Science(all)


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