以正硅酸乙酯（TEOS）和六甲基二硅氮烷（HMDS）为前驱体，研究了引入聚乙烯吡咯烷酮（PVP）对膜层的影响，在碱催化条件下制备了改性的二氧化硅溶胶，并采用提拉涂膜的方法在石英基底上涂膜。对不同组分的薄膜，先经热处理或紫外辐照处理，然后用十八烷基三氯硅烷（OTS）/甲苯溶液对膜层表面进行化学修饰，制备出疏水性能良好的纳米二氧化硅自组装薄膜，分析了不同后处理方法对膜层透过率、接触角、膜层表面微观形貌和激光损伤阈值影响。实验结果表明：溶胶中加入PVP提高了膜层的平整度，经OTS改性后膜层疏水性和激光损伤阈值均得到提高。

Modified SiO2 sols were prepared by base-catalyzed co-hydrolysis and condensation reaction of tetraethylorthosilicate (TEOS) and hexamethyldisilazane (HMDS). The effects of polyvinyl pyrrolidone (PVP) on the properties of coatings were investigated. The single film of SiO2 was deposited on fused silica by dip coating method. The coatings with different components were processed with heat treatment or ultraviolet irradiation, and then modified by the octadecyltrichlorosilane (OTS)/toluene solution. The well water-repellent nano-silica films were obtained by self-assembled technique. The influences of different treatments on films transmission spectra, contact angle, surface morphology and laser damage threshold were analyzed. The results indicated the coatings modified by OTS exhibited excellent hydrophobic properties and the performances of laser damage thresholds were improved. The surface of SiO2 thin film became smoother when PVP was added.