The study of strontium niobium phosphate glass properties and structure

• Main Authors: Jheng-jie Wu, 吳政傑
• Other Authors: none
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/01550867410287929795

碩士 === 國立聯合大學 === 材料科學工程學系碩士班 === 97 === This research choices ternary system strontium niobium phosphate (SrO-Nb2O5-P2O5) glasses as the research object. The main objective to study is based on two systematic phosphate glasses, that to fix P2O5 content and SrO content system, carrying on the adding of Nb2O5 compositions, to confer this glass system of basic property, optics property and structure in systematically. The expectation can understand that glass composition (Nb2O5 content) and the modifier content regarding each property of this glass system. This research expectation establishes a relationship between composition, structure and properties of strontium niobium phosphate glass, as niobium phosphate glass foundation and the basis for research and application. The properties and structure of this glass system are strongly composition dependent. When Nb2O5 content increases in this glass system, increases density, molar volume(Vm), refractive index(nD), glass transition temperature (Tg), glass softening temperature (Td), but decreases thermal expansion coefficient (α) and dissolution rate. The structure of this glass system was examined by Fourier transformed infrared spectroscopy (FTIR), Raman spectrometer(Raman), X-ray photoelectron spectrometer(XPS) and 31P solid state nuclear magnetic resonance (31P MAS-NMR). When Nb2O5 is added into the strontium niobium phosphate glass system, it plays intermediate role, forms P-O-Nb chains and Nb-O-Nb chains. When P2O5≧50mol% , Nb2O5 changes its role from intermediate to modifier, as the adding amount of niobium increases, structure Q3 and Q2 content decreases and changes into Q2 and Q1, forms chaining or the ring structure. When P2O5＜50mol% , Nb2O5 changes its role from intermediate to former, Nb-O-Nb chains and [NbO6]3d chains content increases, Nb5+ substitutes P5+ to become the main structure of this glass system. This research uses uv-visible spectroscopy to discuss visible spectrum absorption level of this glass system. When Nb2O5 and SrO content increases, each glass system visible spectrum shifts to high wavelength. When P2O5/SrO ratio >1, Nb2O5 adds into the strontium niobium phosphate glass system produce a strongly absorption at 400~850nm, absorption intensity is proportional with Nb2O5 content; when P2O5/SrO ratio≦1, visible spectrum has not presented absorption, but transmittance drops slightly.