Investigations on electron beam irradiated rare-earth doped SrF2 for application as low fading dosimeter material: evidence for and DFT simulation of a radiation-induced phase. Issue 32 (21st July 2022)

• Record Type: Journal Article
• Authors: Arnold, Michael; Katzmann, Julia; Naik, Aakash; Görne, Arno L.; Härtling, Thomas; George, Janine; Schuster, Christiane
• Is Part Of: Journal of materials chemistry. Volume 10:Issue 32(2022)
• Page Start: 11579
• Page End: 11587
• Publication Date: 2022-07-21
• Subjects: Materials -- Periodicals; Chemistry, Analytic -- Periodicals; Optical materials -- Research -- Periodicals; Electronics -- Materials -- Research -- Periodicals; 543.0284
• DOI: 10.1039/d2tc01773c
• Languages: English
• ISSNs: 2050-7526

Abstract

Abstract : A recent approach to measure electron radiation doses in the kGy range is the use of phosphors with an irradiation dose-dependent luminescence decay time. Abstract : A recent approach to measure electron radiation doses in the kGy range is the use of phosphors with an irradiation dose-dependent luminescence decay time. However, the applicability of the previously investigated material NaYF4 :Yb 3+, Er 3+ is limited as it shows pronounced fading. Therefore, in this work, a modified SrF2 synthesis is presented that results in SrF2 nanoparticles codoped with Yb and either Er, Hm, or Tm. To assess their suitability as dosimeter material, dose response, as well as its degree of fading over 50 up to 140 days after irradiation were measured. Fading rates as small as 5% in SrF2 :Er, Yb and 4% in SrF2 :Ho, Yb were derived, which are comparable to established dosimeter materials. A combination of spectroscopy, diffraction and DFT calculations was used to elucidate the effect of irradiation, pointing towards the formation of a secondary phase of Yb 2+ that we predict could be Yb2 OF2 . This irreversible formation of a secondary phase is considered to be the explanation for the low fading behavior in SrF2 -based phosphors compared to NaYF4 :Yb, Er, a highly attractive feature for electron beam dosimetry.