An integrated multifunctional membrane via broadband light modulation for greenhouse smart windows

Smart windows that regulate solar irradiation (including ultraviolet UV, visible and infrared) have emerged as an exciting research area for energy conservation, privacy protection and organism healthcare. However, scalable, low cost and robust smart windows with broadband light modulation are still challengeable for practical applications. Here, an integrated smart membrane with capability of managing the light wavelength from UV, visible (Vis) to near infrared (NIR) band via facile spray coating is reported. The smart membrane consists of the upper ITO rich layer, bottom TiO2/SiO2 NPs layer and a bulk elastomeric PDMS as matrix. Due to the NIR reflection and UV absorption, the smart membrane shows high Vis transmittance and moderate UV and NIR transmittance under relaxed state. Due to Mie scattering from vacuum cavity, under stretching (50%), UV, Vis and NIR transmittance could be dramatically decreased from 40% to 5% (380 nm), from 70% to 5% and from 70% to 10%, respectively, indicating highly efficient and sensitive management. In particular, the application in greenhouse exhibits excellent properties in plants protection, IR cooling and privacy preserving. We believe that this work will pave a facile and low-cost approach for a novel class of integrated smart windows via broadband light modulation.