Preparation and characterization of porous silica antireflective coating of high environment stability
SUN Jinghua1,2, DING Ruimin1, ZHANG Cong1,2, ZHANG Ce1,2, XU Yao1
1. Key Laboratory of Carbon Materials, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001, China;
2. University of Chinese Academy of Sciences, Beijing 100049, China
Abstract: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.
[1] Stöber W, Fink A, Bohn E. Controlled growth of monodisperse Silica spheres in the micron size range[J]. Journal of Colloid and Interface Science, 1968, 26(1): 62-69.
[2] Vicente G S, Bayón R, Germán N, et al. Surface modification of porous antireflective coatings for solar glass covers[J]. Solar Energy, 2011, 85 (4): 676-680.
[3] Helsch G, Mös A, Deubener J, et al. Thermal resistance of nanoporous antireflective coatings on silica glass for solar tower receivers[J]. Solar Energy Materials & Solar Cells, 2010, 94(12): 2191-2196.
[4] Xu Y, Zhang L, Wu D, et al. Durable sol-gel antireflective coatings with high laser-induced damage thresholds for inertial confinement fusion[J]. Journal of the Optical Society of America B, 2005, 22(9): 905-912.
[5] Matheron M, Bourgeois A, Gacoin T, et al. Mesoporous 3D-hexagonal organosilicate films: Post-synthesis grafting vs. direct synthesis[J]. Thin Solid films, 2006, 495(1): 175-179.
[6] Bhushan B, Cichomski M. Nanotribological characterization of vapor phase deposited fluorosilane self-assembled monolayers deposited on polydimethylsiloxane surfaces for biomedical micro-/nanodevices[J]. Journal of Vacuum Science & Technology A, 2007, 25(4): 1285-1293.
[7] Born M, Wolf E. Principles of optics[M]. Oxford: Pergamon Press, 1983: 87.
[8] Liu Y, Shen J, Zhou B. Effect of hydrophobicity on the stability of solgel silica coatings in vacuum and their laser damage threshold[J]. Journal of Sol-Gel Science and Technology, 2013, 68(1): 81-87.
[9] Faustini M, Nicole L, Boissière C, et al. Hydrophobic, antireflective, selfcleaning, and antifogging sol-gel coating: An example of multifunctional nanostructured materials for photovoltaic cells[J]. Chemistry of Materials, 2010, 22(15): 4406-4413.
[10] 晏良宏, 匙芳廷, 蒋晓东, 等. 疏水疏油二氧化硅增透膜的制备[J]. 无机材料学报, 2007, 22(6): 1247-1250. Yan Lianghong, Shi Fangting, Jiang Xiaodong, et al. Preparation of hydro-oleophobic silica antireflective coating[J]. Journal of Inorganic Materials, 2007, 22(6): 1247-1250.
[11] 张清华, 杨伟, 马红菊, 等. 含氟有机硅改性多孔二氧化硅减反膜[J]. 光学学报, 2009, 6(29): 1719-1723. Zhang Qinghua, Yang Wei, Ma Hongju, et al. Modification of porous silica antireflective coatings with fluorine-containing organosilicon[J]. Acta Optica Sinica, 2009, 6(29): 1719-1723.