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首页> 外文期刊>Journal of Non-Crystalline Solids: A Journal Devoted to Oxide, Halide, Chalcogenide and Metallic Glasses, Amorphous Semiconductors, Non-Crystalline Films, Glass-Ceramics and Glassy Composites >Preparation and characterization of lead and zinc tellurite glasses
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Preparation and characterization of lead and zinc tellurite glasses

机译：铅锌碲玻璃的制备与表征

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摘要

Glasses of two systems: xPbO-(100 - x)TeO2 (x = 13, 15, 17, 19 and 21 mol%) and yZnO-(100 - y)TeO2 (y = 18, 20, 22, 25, 30, 33 and 35 mol%) were prepared at two melt-cooling rates and characterized by density, UV-visible and Raman spectroscopy, DSC and XRD measurements. ZnO produces a larger compaction in the tellurite network than PbO. Density decreases with melt-cooling rate in both glass series. DSC studies found that the glass transition temperature decreases with increase in PbO concentration in lead tellurite glasses, but increases with increase in ZnO concentration in zinc tellurite glasses. Lead tellurites prepared at higher cooling rates were mostly amorphous while samples containing 19 and 21 mol% of PbO, prepared at slower cooling rates were translucent glass-ceramics containing crystals of PbTeO3, Pb2Te3O8 and TeO2. These slowly cooled samples exhibit an absorption shoulder in the UV-visible absorption spectra, just below the absorption edge. This is attributed to excitonic transitions in nanocrystals that coexist with glassy phase in slowly cooled samples. Raman scattering studies found that the addition of PbO and ZnO produces an increase in the intensity of the absorption band between 720 and 745 cm(-1) relative to the intensity of band between 645 and 670 cm(-1). This is due to the continuous distortion of symmetry of TeO4 units, leading to the creation of TeO3+1 polyhedron and/or TeO3 trigonal units. Raman studies found a very sharp peak at 76 cm(-1) in both lead and zinc tellurite glasses. The position of this peak was independent of the glass composition.
机译：两种系统的玻璃：xPbO-（100-x）TeO2（x = 13、15、17、19和21 mol％）和yZnO-（100-y）TeO2（y = 18、20、22、25、30，在两个熔体冷却速率下制备了33和35mol％）的聚合物，并通过密度，紫外可见和拉曼光谱，DSC和XRD测量来表征。 ZnO在碲酸盐网络中产生的压实度大于PbO。在两个玻璃系列中，密度均随着熔体冷却速率的降低而降低。 DSC研究发现，碲化铅玻璃中的玻璃化转变温度随PbO浓度的增加而降低，而随着碲锌酸锌玻璃中ZnO浓度的增加而升高。在较高冷却速率下制备的铅碲酸盐大部分为非晶态，而在较低冷却速率下制备的含19和21 mol％PbO的样品为半透明玻璃陶瓷，其中包含PbTeO3，Pb2Te3O8和TeO2晶体。这些缓慢冷却的样品在紫外线可见吸收光谱中的吸收边缘正下方。这归因于在缓慢冷却的样品中与玻璃相共存的纳米晶体中的激子跃迁。拉曼散射研究发现，PbO和ZnO的添加相对于645和670 cm（-1）之间的吸收带强度增加了720和745 cm（-1）之间的吸收带强度。这是由于TeO4单元的对称性不断变形，导致创建了TeO3 + 1多面体和/或TeO3三角单元。拉曼研究发现铅和锌碲酸盐玻璃在76 cm（-1）处都有一个非常尖锐的峰。该峰的位置与玻璃组成无关。

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