Observation of photoluminescence and radioluminescence in Eu and Mn doped NaMgF3 nanoparticles

• Published in: Journal of luminescence 2013-11, Vol.143, p.219-225
• Main Authors: Williams, G.V.M., Janssens, S., Gaedtke, C., Raymond, S.G., Clarke, D.
• Format: Article
• Language: English
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Decay; Distortion; Energy transfer; Exact sciences and technology; Luminescence; Manganese; Materials science; NaMgF3; Nanocrystalline materials; Nanoparticles; Nanopowders; Nanoscale materials and structures: fabrication and characterization; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Photoluminescence; Physics; Quantum efficiency; Radioluminescence
• ISSN: 0022-2313; 1872-7883
• DOI: 10.1016/j.jlumin.2013.05.016

Eu and Mn doped NaMgF3 nanoparticles have been made using a reverse micro-emulsion method. All nanoparticles show Mn2+, Eu2+, or Eu3+ photoluminescence (PL) and radioluminescence (RL) as well as PL from an unidentified defect that does not display RL. The Mn2+ sample contains PL emissions from distorted and undistorted Mn2+ sites but the RL is dominated by the undistorted Mn2+ site. The PL lifetime is lowest for the highest Eu concentration. This may be due to energy transfer from Eu3+ sites in the core to Eu3+ sites near the surface followed by non-radiative decay. However, the possibility that Eu3+ substitution leads to more non-radiative decay sites in the core cannot be excluded. The internal quantum efficiency at 270K is highest for the NaMgF3:1% Eu nanoparticles (76%). The RL is independent of dose after an initial ∼10kGy irradiation. •NaMgF3 nanoparticles were synthesized using a reverse micro-emulsion method.•The nanoparticles were successfully doped with Mn2+ and Eu.•There are two Mn2+ sites but only one displays radioluminescence.•The Eu3+ photoluminescence lifetime decreases with increasing Eu3+ concentration.•A radiation dose independent radioluminescence signal was observed after an initial ∼10kGy predosing.