Large‐Area Electrochromic Devices on Flexible Polymer Substrates with High Optical Contrast and Enhanced Cycling Stability. Issue 2 (10th December 2020)

• Record Type: Journal Article
• Authors: Macher, Sven; Schott, Marco; Dontigny, Martin; Guerfi, Abdelbast; Zaghib, Karim; Posset, Uwe; Löbmann, Peer
• Is Part Of: Advanced materials technologies. Volume 6:Issue 2(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-12-10
• Subjects: cycling stability -- electrochromism -- flexible electrochromic devices -- PEDOT -- Prussian blue; Materials science -- Periodicals; Technological innovations -- Periodicals; Materials science; Technological innovations; Periodicals; 620.1105
• DOI: 10.1002/admt.202000836
• Languages: English
• ISSNs: 2365-709X

Abstract

Abstract: Large‐area electrochromic devices (ECDs) based on a cathodically‐coloring, side chain‐modified poly(3, 4‐ethylene dioxythiophene) (PEDOT) derivative and anodically‐coloring Prussian blue (PB) are assembled by a customized sheet‐to‐sheet (S2S) lamination process. The ECDs with two complementary switching "half‐cells", based on flexible PET‐ITO substrates, offer enhanced optical properties in terms of visible light transmission change (4–53%), contrast ratio (CR = 93.4) and color neutrality (L* = 77.9, a* = −5.9, b* = −0.6) in the bleached state. The cycling stability is monitored for up to 10 000 switching cycles (97% charge retention). The reported optical, electrochemical, and in operando (in situ) spectroelectrochemical data are obtained from small laboratory‐scale ECDs (active area: 5 × 5 cm 2 ). These results, the homogeneity of the large‐area devices and the scalability of the S2S lamination process are confirmed by measurements on the large ECDs with an active area of 45 × 65 cm 2 . This large‐area electrochromic film technology with high optical contrast and enhanced cycling stability offers an excellent perspective for further development and scale‐up towards pilot production and the commercialization of flexible ECDs upon their unique materials and processing characteristics. Abstract : Large‐area electrochromic devices based on PEDOT‐EthC6 and Prussian blue show enhanced electrochromic properties in terms of transmission change, color neutrality in the bleached state and cycling stability (10 000 cycles). The device assembly is scaled‐up via a customized sheet‐to‐sheet lamination process (active area: 45 × 65 cm 2 ). The multilayer assemblies demonstrate excellent functionality and are transferred to a roll‐to‐roll lamination process.