Abstract
Energy-efficient windows are considered as one of the most promising energy saving strategies for buildings. An ideal thermochromic smart window should possess high stability, high transmittance and outstanding mechanical properties. However, existing smart window technologies could not meet these requirements simultaneously. Herein, composite hydrogels containing hydroxyethyl methyl cellulose and thermoresponsive poly(N-isopropylacrylamide) were synthesized and applied to smart windows. These hydrogels exhibited excellent solar modulation (ΔTsol = 74.97%), luminous transmittance (Tlum = 84.98%), and mechanical properties with a reversible compression ratio of up to 74%. Besides, they offered faster response time and superior thermal stability compared to traditional hydrogels. It was demonstrated that the composite hydrogels retained exemplary optical properties after 80 heating–cooling cycles, and PNIPAM/HEMC smart windows showed superior indoor temperature control capability. Compared with normal glass, a typical office building with the produced sample was calculated to show annual energy reductions of 19.2, 28.2, 74.8, and 49.7 kW h m−2 in Beijing, Hong Kong, Bangkok, and Kuala Lumpur, respectively. This study demonstrated a reliable strategy for PNIPAM windows that is promising to save building energy.
| Original language | English |
|---|---|
| Pages (from-to) | 5248-5258 |
| Number of pages | 11 |
| Journal | Journal of Materials Chemistry C |
| Volume | 13 |
| Issue number | 10 |
| DOIs | |
| Publication status | Published - 28 Jan 2025 |
Bibliographical note
Publisher Copyright:© 2025 The Royal Society of Chemistry.
Funding
Yongsheng Yang wishes to thank for funding support from Wuhan Textile University Fund B (K24008, K24061, and K24062). Wenxin Li acknowledges the support from the National Natural Science Foundation of China (No. 52408103). Yujie Ke acknowledges the start-up funding support from Lingnan University, Hong Kong.