无铅红外高折射率材料(Bi,Sb)2(Te,Se)3的生长与红外光学性质研究

For infrared optical coating used in the satellite-borne remote-sensing instrument, environmentally-friendly coating materials are urgently required. However, the high-concentration free carriers in thin films of Bi2Te3, which is regarded as a Pb-free infrared high-index material, lead to a large extinction coefficient k and hinder its usefulness in infrared optical coating. Nowadays, searching for a material with the high bulk-insulating behavior and low carrier concentration become a focus of concern for coating materials scientists worldwide. An investigation is suggested in our proposal into the application and properties of solid solution (Bi,Sb)2(Te,Se)3, in which the optical constants, refractive index n and extinction coefficient k, of thin films of (Bi,Sb)2(Te,Se)3 will be explored systemically using combinatorial materials synthesis and high-throughput characterization approach, in order to seek an infrared high-index coating material with excellent optical properties and environmental durability in substitute for PbTe, which is used currently as an infrared coating material with the highest refractive index. Moreover, the relationship will disclosed between stoichiometry, crystallographic structure in (Bi,Sb)2(Te,Se)3 and its complex optical constant through first principle calculations. On this basis, the single crystals of (Bi,Sb)2(Te,Se)3 with designated compositions will be grown using Bridgman-Stockbarger method with accelerated crucible rotation technique, furthermore, used in infrared optical coatings in the satellite-borne remote-sensing instrument. The accomplishment of this investigation will develop a new material with independent intellectual property rights and enhence our ability in manufaturing of the coating materials with special purpose.

环境友好的红外高折射率薄膜材料是航天遥感工程急需的新材料，而潜在的无铅材料碲化铋膜层中高自由载流子浓度导致大的消光系数k，阻碍了其在红外光学薄膜中的应用，探索高体相绝缘性和低载流子浓度的材料成为国际关注的焦点。本项申请提出开展无铅红外高折射率材料(Bi,Sb)2(Te,Se)3性质及应用的研究，使用并行合成与高通量表征等组合材料学的方法探索材料体系中全配比的薄膜红外光学常数（折射率n和消光系数k），以寻找一种或几种具有特定配比、光学和空间环境耐受性优异的材料作为不含铅的红外材料，替代目前可供实际使用的高折射率薄膜材料碲化铅。结合第一性原理的理论计算，揭示出元素配比和晶体结构对其红外复折射率影响的机理。并使用加速安瓿旋转技术和Bridgman-Stockbarger方法生长出特定配比的晶体材料，应用于空间红外光学薄膜，形成具有独立知识产权的产品，提升我国具有特殊用途镀膜材料的研究水平。

环境友好的红外高折射率薄膜材料是航天遥感工程急需的新材料，而潜在的无铅材料碲化铋膜层中高自由载流子浓度导致大的消光系数k，阻碍了其在红外光学薄膜中的应用，探索高体相绝缘性和低载流子浓度的材料成为国际关注的焦点。.在本项研究中，我们使用并行合成与高通量表征等组合材料学的方法，系统地探索了(Bi,Sb)2(Te,Se)3材料体系和Sb2Te3-xSex材料体系中元素配比—晶体结构—红外光谱透射率之间的关系，发现硒化锑材料为具有优异的光学和空间环境耐受性的无铅红外高折射率薄膜材料，可以替代目前可供实际使用的高折射率薄膜材料碲化铅。.在此基础上，我们结合第一性原理的理论计算，揭示出(Bi,Sb)2(Te,Se)3材料体系和Sb2Te3-xSex材料体系中元素配比和晶体结构对其红外光学性能影响的机理，并使用加速安瓿旋转技术和Bridgman-Stockbarger方法生长出硒化锑晶体材料，应用于空间红外光学薄膜，形成了具有独立知识产权的产品，提升了我国具有特殊用途镀膜材料的研究水平。