Design and Implementation of Three-Layer Mesoporous Silica Coating for Tri-wavelength Broadband Antireflection by Block Copolymer Assisted Sol–Gel Method

Abstract

A three-layer tri-wavelength broadband antire ective (AR) coating has been successfully fabricated on quartz substrate via a sol-gel route using acid-catalyzed silica sols. An ethylene oxide-propylene oxide-ethylene oxide tribolock copolymer is used as template to prepare ordered mesoporous SiO 2 lms. Assisted by Filmstar thin lm design software, lm thickness for each layer is optimized on the basis of actual optical constants of the three mesoporous silica lms. The three layers generate a reasonable refractive index gradient from air and thus the obtained AR coating possess high transmittance of 99.24%, 99.66% and 99.64% at 351 nm, 527 nm and 1053 nm, respectively. The mesoporous SiO 2 lms with tough skeleton despite different porosity endow the coating good abrasion-resistance, and 1H, 1H, 2H, 2H-Per uorodecyltriethoxysilane is further used to modify the surface of the AR coating, which can improve the experimental stability of the coating. This work provides bene cial references for AR coating production of sol-gel technique.