Thermometric analysis of the near-infrared emission from Er3+ in yttrium silicate powders containing Mg2+

Abstract Here, we investigate erbium (Er 3+ ) doped yttrium silicate powders prepared by combustion synthesis and the effect of magnesium (Mg 2+ ) on its structural and luminescence characteristics for application in optical thermometry in the near-infrared. Surface morphology and structure of the powders were investigated by X-ray powder diffraction, scanning electronic microscopy, infrared Fourier transform and Raman spectroscopy. CW laser excitation at the visible (λ = 532 nm) produced near-infrared emission corresponding to 2 H 11/2  →  4 I 13/2 and 4 S 3/2  →  4 I 13/2 electronic transitions of Er 3+ . Using the luminescence intensity ratio approach, which takes into account the thermal coupling among states 2 H 11/2 and 4 S 3/2 , the optical temperature sensing performance was investigated in the range 298–673 K. Maximum sensitivity of ∼0.001/K was obtained at 510 K for near-infrared emission from the sample containing 8 wt. % of Mg 2+ and 4 wt. % of Er 3+ .