| 학회 |
한국재료학회 |
| 학술대회 |
2008년 봄 (05/22 ~ 05/23, 상록리조트) |
| 권호 |
14권 1호 |
| 발표분야 |
전자재료 |
| 제목 |
Structural Modification of Alkali Tellurite Binary Glass System and its Characterization |
| 초록 |
This paper presents results and observations obtained from a study of optical and thermal property of alkali tellurite. In this work, Fourier Transform infrared (FT-IR) spectra of alkali tellurite glass samples showed the structural modification from TeO4 trigonal bipyramids (tbp) to TeO3 trigonal pyramids (tp), as M2O [M: Li, Na, K] increased. The optical band gaps which were calculated by Tauc’s method were found to be in the range 3.5~3.8 eV. The glass transition temperature (Tg) of Li2O- TeO2 glasses was decreased from 276℃ to 256℃ when Li2O increased up to 25 mol%. This alkali effect on the glass stability (ΔT=Tx-Tg) of alkali tellurite glasses were obtained by using Differential Thermal Analysis (DTA) with a 10℃/min heating. The coefficient of thermal expansion (CTE) was measured by using Thermo Mechanical Analysis (TMA) with slow heating rate after annealing the glass sample. In this study, we have confirmed that optical band gap of alkali tellurite glasses have only depended on their Te-O-Te structural relaxation based on bridging/ non bridging oxygen (BO/NBO) ratio. Contrary to this, thermal properties have related to ionic field strength of Te-O-M and M-O-M bond as well as Te-O-Te breakage depending on BO/NBO ratio. |
| 저자 |
이규호, 김태호, 나영훈, 정영준, 김영석, 류봉기
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| 소속 |
부산대 |
| 키워드 |
Tellurite glass; FT-IR; DTA; CTE; Optical band gap
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| E-Mail |
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