Assembly of methylated hollow silica nanospheres toward humidity-resistant antireflective porous films with ultralow refractive indices

Humidity-resistant antireflective (AR) porous films with ultralow refractive indices were prepared via an one-step sol–gel process by assembly of methylated hollow silica nanospheres (HSNs). The hydrophobicity and refractive indices of silica-based AR porous films could be varied between 66.0° and 115.0°, and between 1.08 and 1.14, respectively, by tuning the MTES/TEOS molar ratios. A possible assembly mechanism was proposed according to the microstructure of methylated HSNs and porous films. The various properties of silica-based AR porous films were investigated and the AR porous film could demonstrate a good AR capability of 97.6% and excellent humidity resistance.