A Comparative Study on Luminescent Thermometry Performance of Dy ³⁺ ‐Doped AMoO ₄ (A = Ca and Sr) Phosphors

The advancement of efficient, contactless temperature probes that offer high sensitivity, well‐defined temperature‐dependent optical features, and inexpensive fabrication has encouraged widespread research in rare‐earth‐based luminescence thermometry. In this study, we examine the influence of the A‐site cation on the thermometric performance of Dy 3+ ‐doped AMoO 4 (A = Ca, Sr) phosphors. Photoluminescence analysis shows that Dy 3+ :CaMoO 4 exhibits stronger excitation and emission intensities compared to the S r ‐based phosphor. Temperature‐dependent PL spectra were recorded between 303 and 503 K, focusing on the two thermally coupled Dy 3+ transitions originating from the 4 I 15/2 and 4 F 9/2 levels. These emissions display opposite temperature responses, enabling the use of their fluorescence intensity ratio for temperature evaluation. The maximum relative sensitivities obtained for Dy 3+ ‐doped CaMoO 4 and SrMoO 4 were 1.02% and 0.66% K −1 , respectively. The favorable sensitivity values indicate that these AMoO 4 phosphors are promising candidates for applications in optical thermometry.