In situ high-temperature X-ray observation of structural changes of tellurite glasses with p-block oxides; ZnO–TeO2 glasses

Abstract The thermal behavior of each of the three x ZnO·(100− x )TeO 2 (where x =10, 20 and 30 mol%) glasses was studied by an in situ high-temperature X-ray diffractometer, using a rapid measurement system, and differential thermal analysis (DTA). DTA results compared with X-ray diffraction data resulted in phase relations, at high temperature, of the three different glasses. The characteristic temperatures (glass transition and crystallization temperatures) determined for the three glasses showed a dependency on the ZnO content. In the three glasses, the α-TeO 2 and ZnTeO 3 were found to crystallize first, followed by the crystallization of Zn 2 Te 3 O 8 . The phases observed at high temperatures in the three glasses were the same, except for an unknown phase found in the 30ZnO·70TeO 2 glass. Existence-temperature ranges of the phases observed in the three glasses were found to be different. The relation between the first crystallization phase and the local structures of the ZnO–TeO 2 glass systems is discussed.