Effect of neutron-irradiation on optical properties of SiO2-Na2O-MgO-Al2O3 glasses

Abstract

Silica based glasses are used as nuclear shielding materials. The effect of radiation on these glasses varies as per the constituents used in these glasses. Glasses of different composition of SiO 2 -Na 2 OMgO-Al 2 O 3 were made by melt casting techniques. These glasses were irradiated with neutrons of different fluences. Optical absorption measurements of neutron-irradiated silica based glasses were performed at room temperature (RT) to detect and characterize the induced radiation damage in these materials. The absorption band found for neutron-irradiated glasses are induced by hole type color centers related to non-bridging oxygen ions (NBO) located in different surroundings of glass matrix. Decrease in the transmittance indicates the formation of color-center defects. Values for band gap energy and the width of the energy tail above the mobility gap have been measured before and after irradiation. The band gap energy has been found to decrease with increasing fluence while the Urbach energy shows an increase. The effects of the composition of the glasses on these parameters have been discussed in detail in this paper.

FTIR structural investigation of gamma irradiated BaO–Na2O–B2O3–SiO2 glasses

“…This work is extended to investigate the effect of varying glass compositions on the infra red spectra. Also, this is in continuation with our previous work where irradiation effects have been investigated on silicate glasses [10,18,19]. …”

“…on interaction with the glass [9]. Therefore, the knowledge of the glass structure before and after irradiation leads to better understanding of the glass structure as well as the changes taking place in structure as result of the interaction with radiation [10].…”

Gamma ray irradiation effects on the optical properties of BaO–Na2O–B2O3–SiO2 glasses

“…This result is further supported by the shifting of absorption band towards higher wavelength and is attributed to the increasing number of nonbridging oxygen (NBO) atoms after breaking. Similar results with gamma irradiation on microscopic glass slide and silicate glasses have been reported by our group [14,15]. The anomalous behavior of Ba1 glass where the band gap shows a decrease up to a dose of 15 kGy and then suddenly increases to 1.16 eV for a high dose of 60 kGy is due to the reason that the heat effect from the energy transferred by gamma radiations at higher dose either removes some of the localized states inside the forbidden gap or results in a decrease in the density of localized states.…”

“…We have earlier reported the gamma ray irradiation effects on silicate glasses and microscopic glass slides [13][14][15]. This is in continuation of our previous work [16] where we have studied infrared spectroscopic properties of the same glass system before and after c-irradiation.…”

Effect of gamma-ray on producing induced colour centres and on positron annihilation lifetime of bismuth-doped zinc sodium borate glasses

“…Therefore, the obtained FTIR data allows concluding that -irradiation causes cyclic effects i.e. firstly break some chemical bonds of BO3 or BO4 and then reforming other bonds of BO4 or BO3 respectively [44,45]. Therefore, gamma irradiation produces a degree of glass network disorder or defects.…”