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Published on: September 26, 2016
A Comprehensive Study of Nuanced Properties of Dy3+-Doped Alkaline Earth Silicates for Noncontact Thermometry
Tejas1, Princy A2, S Masilla Moses Kennedy2
1Department of Physics Manipal Institute of Technology, Manipal Academy of Higher Education, Udupi, Karnataka, India.
Abstract:
Luminescence materials activated with rare-earth ions for use in optical thermometers and lighting have garnered increasing attention in recent times. In this work, the problem has been tried to resolve by preparing Ba2ZnSi2O7: Dy3+phosphor. X-ray diffraction shows their structure as monoclinic which was further confirmed by Rietveld refinement techniques. Optical studies have been done to confirm their luminescence properties. Stimulated at 351 nm, the as-prepared phosphors show blue (469 nm) and yellow (577 nm) emissions. The 4F9/2 ➔ 6HJ (J = 13/2, 15/2) transitions of Dy3+ ions are responsible for these emissions, and they were also utilized to optimize the dopant concentration. The latter has two types of fluorescence intensity ratios and a type of excitation intensity ratio with maximum relative sensitivities of 2.05% K-1 and 1.96% K-1, respectively. Using an optimized phosphor, which exhibits good optical temperature measuring capabilities, a temperature measurement model was constructed using the fluorescence lifetime (FLT), with a maximum value of SR = 5.42% K-1. The generated Dy3+-doped Ba2ZnSi2O7 phosphors can thus be a good option for UV-excitable warm lighting systems and noncontact optical thermometry measurements, in the light of every experimental finding.
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