Hsu Wan-Ju, Huang Pei-Sun, Huang Yi-Chen, Hu Ssu-Wei, Tsao Heng-Kwong, Kang Dun-Yen
Department of Chemical Engineering , National Taiwan University , Taipei 10617 , Taiwan, ROC.
Department of Chemical and Materials Engineering , National Central University , Taoyuan 32001 , Taiwan, ROC.
Langmuir. 2019 Feb 19;35(7):2538-2546. doi: 10.1021/acs.langmuir.8b03738. Epub 2019 Feb 6.
Zeolites are strongly hydrophilic materials that are widely used as water adsorbents. They are also promising candidates for antifogging coatings; however, researchers have yet to devise a suitable method for coating glass substrates with zeolite-based films. Here, we report on a direct wet deposition technique that is capable of casting zeolite films on glass substrates without exposing the glass to highly basic solutions or the vapors used in zeolite synthesis. We began by preparing cast solutions of pure silica zeolite MFI synthesized in hydrothermal reactions of various durations. The solutions were then applied to glass substrates via spin-on deposition to form zeolite films. The resulting zeolite MFI thin films were characterized in terms of transmittance to visible light, surface topography, thin film morphology, and crystallinity. Wetting and antifogging properties were also probed. We found that hydrophilicity and antifogging capability increased with the degree of thin film crystallinity. We also determined that the presence of the amorphous silica in the thin films is critical to transparency. Fabricating high-performance zeolite-based antifogging coatings requires an appropriate composition of zeolite crystals and amorphous silica.
沸石是强亲水性材料，被广泛用作吸水剂。它们也是防雾涂层的有前途的候选材料；然而，研究人员尚未设计出一种用沸石基薄膜涂覆玻璃基板的合适方法。在此，我们报道一种直接湿沉积技术，该技术能够在不使玻璃暴露于高碱性溶液或沸石合成中使用的蒸汽的情况下，在玻璃基板上浇铸沸石薄膜。我们首先制备了在不同持续时间的水热反应中合成的纯硅沸石MFI的浇铸溶液。然后通过旋涂沉积将溶液施加到玻璃基板上以形成沸石薄膜。对所得的沸石MFI薄膜进行了可见光透射率、表面形貌、薄膜形态和结晶度方面的表征。还探究了润湿性和防雾性能。我们发现亲水性和防雾能力随着薄膜结晶度的增加而提高。我们还确定薄膜中无定形二氧化硅的存在对透明度至关重要。制造高性能的沸石基防雾涂层需要沸石晶体和无定形二氧化硅的适当组成。
