Characterization of novel CeO2-B2O3 glasses, structure and properties

Different glasses in the system xCeO(2)-(1 - x)B2O3 were prepared and characterized. Density (D), molar volume (V-m), microhardness (H-v), glass transition temperature (T-g), thermal expansion coefficient (alpha) and infrared measurements of the glasses have been carried out. IR results of CeO2-rich glasses (40-60 mol%) confirm that CeO2 affects the glass network as both a network modifier and a network former. The modifier part of CeO2 is consumed in transformation of BO3 units to BO4 groups. The rest of CeO2 can participate in the network in the form of CeO4 units. Both Tg and H-v increase with increasing the concentration of BO4 and CeO4 units. There is a great change in alpha with increasing CeO2 content. The increase in both T-g and H-v and the decrease in alpha are considered as evidences for increasing the total network connectivity. On the other hand, the concentration of BO4 and CeO4 groups in glasses of lower CeO2 content(< 40mol%) is considered to be limited. This was interpreted in terms of the ability of CeO2 to form linkages with BO3 groups rather than forming BO4 units. (C) 2001 Elsevier Science B.V. All rights reserved.