title: Patternable PEDOT nanofilms with grid electrodes for transparent electrochromic devices targeting thermal camouflage.
abstract: This paper reports a new type of transmitting mode electrochromic device that uses the high-contrast electrochromism of poly(3,4-ethylenedioxythiophene) (PEDOT) and operates at long-wavelength infrared (8-12 μm) . To maximize the transmittance contrast and transmittance contrast ratio of the device for thermal camouflage, we control the thickness of the thin PEDOT layer from 25 nm to 400 nm and develop a design of grid-type counter electrodes. The cyclability can be greatly improved by selective deposition of the PEDOT film on grid electrodes as an ion storage layer without any loss of overall transmittance. The device with optimized architectures shows a high transmittance contrast ratio of 83 % at a wavelength of 10 μm with a response rate under 1.4 s when alternating voltage is applied. Captured images of an LED lamp behind the device prove the possibility of active, film-type camouflage against thermal detection.
authors.affiliation: Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 335 Gwahangno, 305-701 Yuseong-gu, Daejeon Republic of Korea ; KAIST Institute for the Nanocentury, Graphene Research Center, Korea Advanced Institute of Science and Technology (KAIST), 335 Gwahangno, 305-701 Yuseong-gu, Daejeon Republic of Korea.
authors.forename: Bumsoo
authors.initials: B
authors.lastname: Kim
authors.affiliation: Department of Chemical and Biomolecular Engineering, Yonsei University, 262 Seongsanno, 120-746 Seodaemum-gu, Seoul Republic of Korea.
authors.forename: Jong Kwan
authors.initials: JK
authors.lastname: Koh
authors.affiliation: Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 335 Gwahangno, 305-701 Yuseong-gu, Daejeon Republic of Korea ; KAIST Institute for the Nanocentury, Graphene Research Center, Korea Advanced Institute of Science and Technology (KAIST), 335 Gwahangno, 305-701 Yuseong-gu, Daejeon Republic of Korea.
authors.forename: Junyong
authors.initials: J
authors.lastname: Park
authors.affiliation: Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 335 Gwahangno, 305-701 Yuseong-gu, Daejeon Republic of Korea ; KAIST Institute for the Nanocentury, Graphene Research Center, Korea Advanced Institute of Science and Technology (KAIST), 335 Gwahangno, 305-701 Yuseong-gu, Daejeon Republic of Korea.
authors.forename: Changui
authors.initials: C
authors.lastname: Ahn
authors.affiliation: Agency for Defense Development (ADD), 305-152 Yuseong-gu, Daejeon Republic of Korea.
authors.forename: Joonmo
authors.initials: J
authors.lastname: Ahn
authors.affiliation: Department of Chemical and Biomolecular Engineering, Yonsei University, 262 Seongsanno, 120-746 Seodaemum-gu, Seoul Republic of Korea.
authors.forename: Jong Hak
authors.initials: JH
authors.lastname: Kim
authors.affiliation: Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), 335 Gwahangno, 305-701 Yuseong-gu, Daejeon Republic of Korea ; KAIST Institute for the Nanocentury, Graphene Research Center, Korea Advanced Institute of Science and Technology (KAIST), 335 Gwahangno, 305-701 Yuseong-gu, Daejeon Republic of Korea.
authors.forename: Seokwoo
authors.initials: S
authors.lastname: Jeon