The porous silica optical antireflective coating is prepared by the sol-gel method with the tetraethoxylsilane as the precursor and the ammonia as the catalyst via a dip-coating process. The environment stability of the antireflective coating could be greatly improved by post-grafting 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane (FAS-17) and hexamethyldisilazane (HMDS). The properties of the coating are characterized by the UV-VIS spectrometer, the FTIR spectrophotometer, the atomic-force microscopy, the contact angle measurement and the anti-pollution test. The results indicate that for the modified coating, the peak transmittance is up to 99.82%, the surface roughness is only 3.9 nm, and, the contact angle with water is 125°. Especially, the decrease of the transmittance when being tested with water and polydimethylsiloxane pollution in vacuum for two months is as small as 0.03%, suggesting that the coating has an excellent environment stability.

sol-gel method  /  porous silica  /  antireflective coating  /  environment stability  /  FAS-17  /  HMDS