Effects of oxygen vacancies on luminescence characteristics of BeO ceramics

Altunal V., Guckan V., Yegingil Z.

JOURNAL OF ALLOYS AND COMPOUNDS, cilt.938, 2023 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 938
  • Basım Tarihi: 2023
  • Doi Numarası: 10.1016/j.jallcom.2022.168670
  • Dergi Adı: JOURNAL OF ALLOYS AND COMPOUNDS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, PASCAL, Aerospace Database, Chemical Abstracts Core, Communication Abstracts, INSPEC, Metadex, Public Affairs Index, Civil Engineering Abstracts
  • Anahtar Kelimeler: Beryllium oxide (BeO), Oxygen deficiency, Optically stimulated luminescence (OSL), Thermoluminescence (TL), Photoluminescence (PL), Electron spin resonance (ESR)
  • Çukurova Üniversitesi Adresli: Evet

Özet

Understanding whether the luminescence of BeO ceramics synthesized by co-precipitation technique is due to oxygen vacancies (Vo) or not is very important concerning the development of this material as an OSL dosimeter. This study investigates the effect of oxygen vacancies in undoped and alkali-metal doped BeO ceramics, on luminescence properties following laboratory and argon sintering processes. We created oxygen deficiencies in the BeO-based ceramics and obtained high-sensitivity OSL dosimeters. Considering that Vo defects are formed by sintering in an inert gas environment, we compared the structural and luminescence properties of this material with that of sintered in the air atmosphere. The crystallite properties of undoped and alkali-metal-doped BeO ceramics were defined by XRD analysis. The presence of Vo defects was confirmed by ESR analyses. On the other hand, smoother and non-porous surface structures were observed in SEM images. We observed an emission band originating from Vo appearing between 600 and 800 nm in BeO(Vo) ceramics in comparison with the RL signals of BeO ceramics. In addition, it was observed that the characteristic BeO emission band located between 200 and 400 nm increased significantly with sintering in an argon gas environment. A remarkable enhancement for TL and OSL signals was observed in BeO(Vo), BeO:Na5%(Vo), BeO:Li5%(Vo), and BeO:K5%(Vo) ceramics when compared with the BeO, BeO:Na, BeO:Li, and BeO:K ceramics. Through this study, it can be concluded that the source of luminescence of BeO ceramics may originate from the oxygen vacancies that occur during synthesis in the structure. Eventually, the significant enhancement in luminescence from undoped and alkali-metal doped BeO ceramics can be controlled by applying the appropriate conditions during the synthesis.