Xia Bibo, Yan Lianghong, Li Yuanyang, Zhang Shuming, He Meiying, Li Hao, Yan Hongwei, Jiang Bo
Key Laboratory of Green Chemistry & Technology, College of Chemistry, Sichuan University Chengdu 610064 P. R. China
Research Center of Laser Fusion, China Academy of Engineering Physical Mianyang 621900 P. R. China
RSC Adv. 2018 Feb 7;8(11):6091-6098. doi: 10.1039/c7ra12817g. eCollection 2018 Feb 2.
Silica coatings with continuously adjustable refractive indices and wettability properties were prepared through a sol-gel base-catalyzed process. Adjustment of the molar ratio of water (HO) to tetraethylorthosilicate (TEOS) was utilized to change the hydrolysis degree of the precursors, and hence change the morphology of the silica particles. With the increase in the HO/TEOS molar ratio, the morphology of the silica particles changed from a linear net-work structure to a bead-like structure and then to a granular particle structure. A particle growth mechanism was proposed and verified by characterization. As the HO/TEOS molar ratio increased from 0.3 to 21.0, the refractive indices of the silica coatings increased from 1.132 to 1.328. Meanwhile, a varied HO/TEOS molar ratio also modulated the surface wettability of the silica coatings. The static water angle of the silica coatings decreased from 145° to 6° by increasing the HO/TEOS molar ratio from 0.3 to 21.0. Different hydrophilic and hydrophobic coatings could be obtained by simply controlling the HO/TEOS molar ratio. Silica coatings with different refractive indices and hydrophobic (or hydrophilic) properties were obtained at different HO/TEOS molar ratios.
通过溶胶 - 凝胶碱催化工艺制备了具有连续可调折射率和润湿性的二氧化硅涂层。利用水（HO）与正硅酸乙酯（TEOS）摩尔比的调节来改变前驱体的水解程度，进而改变二氧化硅颗粒的形态。随着HO/TEOS摩尔比的增加，二氧化硅颗粒的形态从线性网络结构变为珠状结构，然后变为颗粒状结构。提出了一种颗粒生长机制并通过表征进行了验证。随着HO/TEOS摩尔比从0.3增加到21.0，二氧化硅涂层的折射率从1.132增加到1.328。同时，不同的HO/TEOS摩尔比也调节了二氧化硅涂层的表面润湿性。通过将HO/TEOS摩尔比从0.3增加到21.0，二氧化硅涂层的静态水接触角从145°降至6°。通过简单地控制HO/TEOS摩尔比，可以获得不同的亲水和疏水涂层。在不同的HO/TEOS摩尔比下获得了具有不同折射率和疏水（或亲水）性质的二氧化硅涂层。
