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Abstract Smart windows are energy‐efficient windows whose optical transparency can be switched between highly transparent and opaque states in response to incident solar illumination. Transparent and conductive metal nanomesh (NM) films are promising candidates for thermochromic smart windows due to their excellent thermal conductivity, high optical transparency at near infrared wavelengths, and outstanding stability. In this study, ZnO/Au/Al2O3NM films with periodicities of 200 and 370 nm are reported. The ZnO/Au/Al2O3NM film with a 370 nm periodicity exhibits a transmittance over 90% at 550 nm and sheet resistance lower than 20 Ω sq−1. Based on a standard figure of merit, this structure outperforms current state‐of‐the‐art NM films. Here, the integration of ZnO/Au/Al2O3NM films into a thermochromic perovskite smart window is also demonstrated. The transparency of the smart window structure is manipulated by transient resistive heating to trigger the thermochromic transition to the opaque state, which can be then maintained solely by 1‐sun, AM 1.5 G illumination. This climate‐adaptive, low power‐activated, and fast‐switching smart window structure opens new pathways toward its practical application in the real world.
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Assessing the Performance of a Thermoresponsive Liquid‐Based Smart Windows for Building Thermal Regulation through Outdoor Experimentation and Computational Modeling
Abstract Smart windows have the potential to respond dynamically and passively to external stimuli, controlling the amount of light passing through the window. When a smart window switches from a clear to a translucent state, energy flow through the window is partially attenuated, allowing a room to cool down passively, thereby reducing the energy and fossil fuel consumption for air conditioning. The smart window demonstrated here consists of a thermoresponsive liquid consisting of Tergitol 15‐S‐7, which can dynamically and passively switch the window's transmittance when a temperature of 39 °C is reached. It is also demonstrated how the transition temperature can be lowered by adding salts. Outdoor experiments in realistic environments show that the temperature of a model house built with a thermo‐responsive window can achieve an indoor temperature of 7 °C less than a control house with an ordinary window. This study quantifies the energy savings possible using such windows at the building scale for cooling and heating in different climates and times of the year.
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- Award ID(s):
- 1944323
- PAR ID:
- 10640760
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Sustainable Systems
- Volume:
- 8
- Issue:
- 9
- ISSN:
- 2366-7486
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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