Effect of NiO and Light Intensity on Dielectric Constant of SiO₂-B₂O₃-Bi₂O₃-Na₂CO₃ Glass Based on Silica Gel of Natural Sands

The use of silica in various fields is significantly increasing. One common application is silica based functional glass which has naturally show specific dielectric, optical, and magnetic properties. Many studies have been performing to explore the influence of dopant, composition, and other processing parameters as well as employing various characterization. In the previous work, we report the use of silica from silica sands. To reduce the melting temperature, we used silica sol-gel beside the utilization of some oxides such as B₂O₃, Na₂CO₃, and Bi₃O₃. We also used NiO as dopant explore the glass properties. We have prepared a series of sample with the composition of 50SiO₂-25B₂O₃-(6.5-x) Bi₃O_3-18.5 Na₂CO₃-xNiO (x = 0, 1, 2, 3 and 4 wt%). After weighting process, the composition was blended, then heated to 450 °C for 120 minutes and then raised at 950 °C for 60 minutes in the crucible. Then samples of glass separated from the crucible and in the characterization of the structure using the DTA, XRD, SEM-EDAX and FTIR and measuring dielectric constant using a capacitance meter. The increase of NiO dopant resulted in increasing the dielectric constant of glass. On the other hand, the dielectric constant gradually decreases with the increase of light intensity. One can be noted that the applied intensity give rise to the step-like decrease of the dielectric constant. Whereas, the increasing magnetic field indicate the increase of dielectric constant. (paper)