Electrically tunable window based on microwrinkled ZnO/Ag thin film
Micro-winkling can turn a transparent thin-film of zinc oxide (ZnO) to be ‘opaque’ that can be reversed by unfolding to restore back to the clear state. This principle was previously used to make a mechanically tunable window device. However, ZnO thin film cannot make a compliant electrode to enable...
| Main Authors: | , , |
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| Format: | Conference Paper |
| Language: | English |
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2019
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| Online Access: | https://hdl.handle.net/10356/82293 http://hdl.handle.net/10220/47507 |
| _version_ | 1811688481797177344 |
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| author | Shrestha, Milan Asundi, Anand Lau, Gih-Keong |
| author2 | Bar-Cohen, Yoseph |
| author_facet | Bar-Cohen, Yoseph Shrestha, Milan Asundi, Anand Lau, Gih-Keong |
| author_sort | Shrestha, Milan |
| collection | NTU |
| description | Micro-winkling can turn a transparent thin-film of zinc oxide (ZnO) to be ‘opaque’ that can be reversed by unfolding to restore back to the clear state. This principle was previously used to make a mechanically tunable window device. However, ZnO thin film cannot make a compliant electrode to enable electrical unfolding due to its insulator nature. This paper reports the use of multilayer thin films of 10nm silver (Ag) and 30nm thick ZnO to form a compliant electrode with electrically tunable transmittance. A dielectric elastomer actuator (DEA) with a pair of such compliant Ag/ZnO thin films on both sides of a polyacrylate elastomeric membrane (3M VHB 4910) makes an electrically tunable window device. The DEA without radial compression of the elastomer has wrinkle-free electrode. Hence, it is clear with a 47% in-line transmittance (for 550nm wavelength light). In the wrinkled form, under 10% radial compression, it becomes opaque (with less than 1% transmittance). A voltage induced areal expansion of 10% radial strain enables the electrical unfolding of the initial wrinkles. In addition, this device continues to work after 4000 cycles of unfolding and microwrinkling of Ag/ZnO. The performance of electrically tunable window device is comparable to the existing smart window technologies. |
| first_indexed | 2024-10-01T05:32:54Z |
| format | Conference Paper |
| id | ntu-10356/82293 |
| institution | Nanyang Technological University |
| language | English |
| last_indexed | 2024-10-01T05:32:54Z |
| publishDate | 2019 |
| record_format | dspace |
| spelling | ntu-10356/822932023-03-04T17:07:38Z Electrically tunable window based on microwrinkled ZnO/Ag thin film Shrestha, Milan Asundi, Anand Lau, Gih-Keong Bar-Cohen, Yoseph School of Mechanical and Aerospace Engineering SPIE Smart Structures and Materials + Nondestructive Evaluation and Health Monitoring Singapore Centre for 3D Printing Transparency Tuning Smart Window DRNTU::Engineering::Mechanical engineering Micro-winkling can turn a transparent thin-film of zinc oxide (ZnO) to be ‘opaque’ that can be reversed by unfolding to restore back to the clear state. This principle was previously used to make a mechanically tunable window device. However, ZnO thin film cannot make a compliant electrode to enable electrical unfolding due to its insulator nature. This paper reports the use of multilayer thin films of 10nm silver (Ag) and 30nm thick ZnO to form a compliant electrode with electrically tunable transmittance. A dielectric elastomer actuator (DEA) with a pair of such compliant Ag/ZnO thin films on both sides of a polyacrylate elastomeric membrane (3M VHB 4910) makes an electrically tunable window device. The DEA without radial compression of the elastomer has wrinkle-free electrode. Hence, it is clear with a 47% in-line transmittance (for 550nm wavelength light). In the wrinkled form, under 10% radial compression, it becomes opaque (with less than 1% transmittance). A voltage induced areal expansion of 10% radial strain enables the electrical unfolding of the initial wrinkles. In addition, this device continues to work after 4000 cycles of unfolding and microwrinkling of Ag/ZnO. The performance of electrically tunable window device is comparable to the existing smart window technologies. Published version 2019-01-17T06:43:00Z 2019-12-06T14:52:40Z 2019-01-17T06:43:00Z 2019-12-06T14:52:40Z 2017 Conference Paper Shrestha, M., Asundi, A., & Lau, G.-K. (2017). Electrically tunable window based on microwrinkled ZnO/Ag thin film. SPIE Smart Structures and Materials + Nondestructive Evaluation and Health Monitoring, 10163, 101631Y-. doi:10.1117/12.2259918 https://hdl.handle.net/10356/82293 http://hdl.handle.net/10220/47507 10.1117/12.2259918 en © 2017 Society of Photo-optical Instrumentation Engineers. All rights reserved. This paper was published in SPIE Smart Structures and Materials + Nondestructive Evaluation and Health Monitoring and is made available with permission of Society of Photo-optical Instrumentation Engineers. 8 p. application/pdf |
| spellingShingle | Transparency Tuning Smart Window DRNTU::Engineering::Mechanical engineering Shrestha, Milan Asundi, Anand Lau, Gih-Keong Electrically tunable window based on microwrinkled ZnO/Ag thin film |
| title | Electrically tunable window based on microwrinkled ZnO/Ag thin film |
| title_full | Electrically tunable window based on microwrinkled ZnO/Ag thin film |
| title_fullStr | Electrically tunable window based on microwrinkled ZnO/Ag thin film |
| title_full_unstemmed | Electrically tunable window based on microwrinkled ZnO/Ag thin film |
| title_short | Electrically tunable window based on microwrinkled ZnO/Ag thin film |
| title_sort | electrically tunable window based on microwrinkled zno ag thin film |
| topic | Transparency Tuning Smart Window DRNTU::Engineering::Mechanical engineering |
| url | https://hdl.handle.net/10356/82293 http://hdl.handle.net/10220/47507 |
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