Effect of Bi2O3 on the structure and thermal properties of Bi2O3-SiO2-B2O3 glasses prepared by sol-gel method

Bi2O3-SiO2-B2O3 low-melting glass powders with different Bi2O3 contents (45-60 mass%) are synthesized using sol-gel method. The structure, crystallization behavior, thermal properties, chemical stability and physical characteristics of the samples are systematically investigated. The broad peak in X-ray diffraction patterns confirms the amorphous properties of all the glass samples. The infrared absorption spectra analysis shows that [BiO3], [BiO6], [BO3] and [BO4] are the main structure units of the glass powders. The [BO3] groups are converted into more stable [BO4] groups with rising the Bi2O3 content. The glass transition temperature (T-g) decreases from 478.56 to 456.24 degrees C when the Bi2O3 contents increases from 45 to 60 mass%. Both the glass softening temperature (T-f) and the crystallization temperature (T-p) decline with the increase of Bi2O3 content. In addition, the results revealed that the chemical stability decreases gradually and the volume resistivity of glass powders decreases from 3.08 x 10(14) Omega cm to 2.04 x 10(11) Omega cm as the content of Bi2O3 increases. [GRAPHICS] .