透明多孔氧化锌薄膜的制备及其光学性能的研究

Synthesis and Property Characterization of Sol-Gel Porous ZnO Coatings

采用溶胶-凝胶模板法,以二合水醋酸锌为前驱体,二乙醇胺为稳定剂,引入模板剂聚二乙醇获得多孔氧化锌薄膜。借助于扫描电镜、透射电镜、X射线衍射等手段,对薄膜的微观组织结构、生长过程和光学性能进行研究,并分析了模板剂对薄膜生长的溶胶-凝胶过程的影响。研究结果表明,加入适量模板剂后易获得多孔结构、结晶良好的薄膜。随浓度增加孔道逐渐向蠕虫状转变,孔隙率有所下降,多孔薄膜的折射率处于1.5~1.7范围,透射率可提高到95%以上,薄膜的光学性能进一步提高。

The transparent porous ZnO thin filmswere deposited on glass substrate in sol-gel method with zinc acetate,DEAand PEG2000 as the precursor,stabilizer and template,respectively. The influence of the template on the microstructures,porosity and optical properties of the ZnO coatings were investigated X-ray diffraction,scanning electron microscopy,transmission electron microscopy and conventional optical spectroscopy. The results show that the template agent concentration has a major impact on the microstructures and optical properties of the ZnO coatings. For example,as the template agent concentration increased,the randomly distributed micro-pores changed into vermicular-shaped,interconnected larger pores,accompanied by a decrease of porosity. Grown in diffusion limited aggregation mode and with an optimized template agent concentration,the porous polycrystalline ZnO coatings,consisting of preferentially oriented columnar grains,displayed a refractive index in the range of 1. 5 ~ 1. 7 and a transmittance in 85% ~ 95% range.