用传统熔融淬冷法制备了新型远红外Te基硫系玻璃(100-x)(GeTe4)-xGa(x=0,5,10mol%).利用差热分析(DTA)、可见/近红外吸收光谱、红外透射光谱等技术,在GeTe4玻璃的基础上,通过引入较高配位金属Ga,研究其对玻璃组成、结构和性能的影响,利用经典的Tauc方程计算了样品光学带隙允许的直接跃迁、允许的间接跃迁及Urbach能量.分析结果表明:在GeTe4玻璃中引入Te—Ga键,减少Te的金属性,提高了Te玻璃的形成能力.当Ga的含量为10mol%时,玻璃热稳定性最好.随着Ga含量的加入,玻璃的红外透过性能得到提高,红外截止波长达到20μm;利用金属标准和平均键能等相关理论,讨论了玻璃光学带隙与组分变化的关系,结果表明光学带隙按照特定函数关系递减.
A series of (100-x)(GeTe4)-xGa (x = 0,5,10 mol% ) far infrared transmitting chalcogenide glasses is prepared by the traditional melt-quenching method.In this paper,the differential thermal analysis (DTA),visible/near-infrared absorption spectroscopy,infrared transmission spectra are adopted to analyze composition,structure and performance of the GeTe4 glass system with the addition of Ga.The results show that the Te-Ga bond is formed,which can reduce Te metallic character.When the content of Ga is 10 mol% ,the glass is of the best thermal stability.With the addition of Ga,the transmission percentage is improved and infrared cut-off wavelength of the glasses extends beyond 20 μm.Based on the metallization criterion and average bond energy,the relationship between optical band gap and composition is investigated.