TiO_2/SiO_2多层膜的带隙结构及光催化性能

Band Gap Properties and Photocatalytic Activities of TiO_2/SiO_2 Multilayer Film

利用传输矩阵法设计了由SiO2、TiO2组成的多层膜高透射率光子晶体结构,并分析了其透射谱特性,根据等效层原理改变多层膜一维光子晶体的自身结构来提高通带内特征波长附近的透射率,获得了最佳结构参数。研究结果表明,当晶格参数为150nm,填充比为0.346,周期数为6时,400nm波长附近吸收带处的透射率最低也可达96.5%,并且不论是TM模式还是TE模式,入射角在0°～45°范围内仍保持高的透射率,该结构可望用于空气净化装置以提高SiO2、TiO2光催化剂的光催化效率。

By using the transfer-matrix method,the multilayer films of photonic crystal composed of SiO2 and TiO2 with high-transmissivity are designed.The characteristics of transmission spectra of the multilayer films are studied.Based on the theory of equivalent layer,the structure of photonic crystal is modified to improve the transmittance in the pass band around specific wavelength,and the optimal parameter is obtained.The results indicate that the minimum transmittance of the optimal structure with lattice paramenter of 150 nm,filling ratio of 0.346 and periodicity of 6,is also up to 96.5% at 400 nm.No matter the incident wave is TM model or TE model,the transmittance do not change significantly,when the incident angles changes from 0° to 45°.The structure can be used for air purification device to improve the photocatalytic efficiency of SiO2 and TiO2 films.