Luminescence and optical thermometry based on silico-carnotite Ca3Y2Si3O12: Pr3+ phosphor

The photoluminescence and temperature sensitivities of Ca₃Y₂Si₃O₁₂:Pr³⁺ thermo-phosphors with silico-carnotite structure obtained by solid state reaction method were investigated. Pr³⁺ ions were accommodated in the A sites having coordination number of 9 in AB₂C₂(SiO₄)₃ to replace Y³⁺ ions. The typical sample consisted of microcrystals with an irregular structure and the surface of particles was smooth, which could enhance the luminescence due to reducing the scattering and non-radiation produced by rough surfaces. The band gap value of typical sample was about 4.01 eV. Dipole-dipole interaction could account for concentration quenching. The two thermometry strategies including normalized intensities from ³P₀→³H₄ transition and Fluorescence intensity ration (FIR) of ³P₀→³H₄/³P₁→³H₅ transitions were employed for temperature sensing in 298–573 K. The results revealed that Ca₃Y₂Si₃O₁₂:Pr³⁺ thermo-phosphors had good temperature sensitivity performance with maximum S_r of 0.59% K^?1@573 K and 0.762% K^?1@298 K in the above two methods, respectively. Hence, Ca₃Y₂Si₃O₁₂:Pr³⁺ would be a promising candidate in the field of optical thermometry.