UV effect on the cathodo- and thermoluminescence properties of a gem-quality Cr-rich diaspore (α-AlOOH). (November 2018)

• Record Type: Journal Article
• Authors: Topaksu, M.; Correcher, V.; Boronat, C.; Garcia-Guinea, J.; Portakal, Z.G.; Akça, S.
• Is Part Of: Applied radiation and isotopes. Volume 141(2018:Nov.)
• Page Start: 101
• Page End: 106
• Publication Date: 2018-11
• Subjects: Diaspore -- Thermoluminescence -- Cathodoluminescence -- Dose response -- UVC; Radiology -- Periodicals; Radiation -- Industrial applications -- Periodicals; Nuclear chemistry -- Periodicals; Internet resource; Periodical; 660.298
• DOI: 10.1016/j.apradiso.2018.08.025
• Languages: English
• ISSNs: 0969-8043

Abstract

Abstract: This work reports on the cathodoluminescence (CL) and thermoluminescence (TL) properties of gem-quality diaspore samples from Milas/Muğla (Turkey) after 100 h of ultraviolet-C (UVC) exposure. The UVC exposure induces significant changes in the intensity of the CL emission in the range of 400–800 nm that would be mainly associated with photo-oxidation processes of the impurities (Cr 3+, Ti 3+, Fe 2+ ) that substitute for Al 3+ in the diaspore (α-AlOOH) lattice. The UVC effect on the 400 nm-TL behavior of beta irradiated samples in the range of 0.1–8 Gy modifies the TL glow curves probably due to both photo-transfer process where electrons release from deeper to shallower traps and redox reactions involving, also, breakages-linkages of chemical bonds. Meanwhile, the 'as received' samples consist of three maxima centered at about 120, 180, and 234 °C, the 100 h UVC-irradiated samples display three maxima at 122, 220 and 270 °C. The physical trapping parameters (intensity and peak position, trap depth and pre-exponential factor) for each TL curve were estimated by using a computerized glow curve analysis program. Highlights: CL and TL properties of gem-quality diaspore samples were determined after 100 h of UVC exposure. The UVC exposure induces significant changes in the intensity of the CL. The 100 h UVC-irradiated and as received samples display three maxima. The physical trapping parameters were estimated by using GCA program.