玻璃表面梯度多孔减反射膜层的水热制备及水刻蚀剂添加Na_(2) HPO_(4)对膜层结构的影响

Hydrothermal Preparation of Gradient Porous Antireflection Film on Glass Surface and the Effect of Na_(2)HPO_(4) Added into Water Etching Agent on Film Structure

玻璃表面梯度多孔减反射膜层具有超低反射率、可实现可见光高增透率的特性,在光伏、电子显示、汽车等领域有广阔的应用前景。玻璃在水热过程中与水反应激烈,表面难以形成梯度多孔结构的膜层。如何通过调控刻蚀液,减缓玻璃的刻蚀反应,形成梯度多孔结构的表面膜层,是水热法制备梯度多孔减反射膜层必须克服的技术问题。本工作以商用三种钠钙硅玻璃为基底,分别以水和Na_(2)HPO_(4)水溶液为刻蚀剂,通过水热法成功制备了梯度多孔减反射膜层,分析了刻蚀膜层的微观形貌、元素分布、红外光谱以及玻璃的光学性能。通过Macleod和TFCalc软件进行了膜层的折射率和反射率数值模拟。以水为刻蚀剂,得到微米级凹凸表面。水刻蚀剂添加Na_(2)HPO_(4),所得膜层为梯度多孔减反射膜层。添加的Na_(2)HPO_(4)起减缓刻蚀反应、构筑多孔刻蚀膜层作用,其最佳添加量与玻璃碱土金属含量呈反向相关关系。反射率R 380~780 nm最低达到0.88%,增透ΔT 380~780 nm最高达到7.39%。

Gradient porous antireflection film on glass surface,as characterized by the ultra-low reflectance and high increasing transmittance of visible light,has a wide range of application prospects in photovoltaic,electronic display,automotive and other fields.Glass reacts strongly with water during hydrothermal process,resulting in difficulty forming gradient porous structural film on the surface.One of the important technical problems in the preparation of gradient porous antireflection film by hydrothermal method is how to control the etching solution to slow down the etching reaction of glass,eventually forming the surface film with gradient porous structure.In this work,gradient porous antireflection film on glass surface has been successfully prepared by a hydrothermal method,using water and Na_(2)HPO_(4) solution as etching agents,and three commercial sodalime glasses as substrates.The etched film’s microscopic morphology,element distribution,infrared spectroscopy and the glass’s optical properties were analyzed.The etched film’s refractive index and reflectance were simulated by Macleod and TFCalc software,respectively.The micron concave and convax surface was obtained when water etching agent was used.However,gradient porous antireflection film has been prepared when Na_(2)HPO_(4) was added into water etching agent.The added Na_(2)HPO_(4) contributes to slowing down etching reaction and constructing porous etched film.The best addition volume of Na_(2)HPO_(4) demonstrates a reverse relationship with the glass’s alkaline-earth metal content.The lowest reflectance R 380—780 nm is 0.88%,and the highest increasing transmittanceΔT380—780 nm reaches 7.39%.