Synthesis of hydrophobic W18O49 nanorods for constructing UV/NIR-shielding and self-cleaning film

Abstract Nanomaterials with ultraviolet/near-infrared (UV/NIR) shielding property have great potential for developing energy-saving windows. In this work, we report low-cost W18O49 nanorods as UV/NIR shielding material. W18O49 nanorods with the length of ∼20 or ∼60 nm were prepared by simple solvothermal method, and they exhibited strong size-dependent absorption in the UV/NIR region. By mixing W18O49 nanorods with polydimethylsiloxane (PDMS), W18O49@PDMS films were constructed and they could shield 55.58% of UV and 75.89% of NIR light while transmit 58.03% of visible light. A sealed box with W18O49@PDMS-coated glass as the window exhibited a minimal temperature elevation (△T = 9.2 °C) compared to those coated with pure glass (△T = 18.2 °C) or ITO glass (△T = 12.1 °C), under the irradiation of solar light (0.6 W cm−2). Additionally, the films had a contact angle of 122 ± 2°, showing self-cleaning ability. Therefore, W18O49@PDMS films can act as cost-efficient UV/NIR-shielding and self-cleaning film.