In this study, we investigated the structural, optical, concentration, and temperature-sensitive luminescence properties of praseodymium (Pr3⁺)-doped Ca2Al2SiO7 phosphors synthesised via a urea-assisted combustion method. Rietveld refinement and XRD analyses confirmed the formation of a tetragonal phase with a P͞421m space group. The energy band gap was 4.430 \(\pm\) 0.124 eV, and DRS analysis confirmed different transitions of Pr3+ ions. The concentration dependency of the emission was explored using room-temperature PL, where the optimum performance was observed for a dopant concentration of 4 mol%. The UVC emission of Pr3+ ions is associated with the 4f15d1 → 3HJ and 3F2 energy levels, and the decay lifetime is in the range of 7.3–8 μs. The emission intensity decreased with increasing temperature, indicating temperature quenching. A high quenching temperature (412 K) and a high activation energy of 0.258 \(\pm\) 0.016 eV were obtained for the CASO-4 Pr phosphor, confirming its exceptional thermal stability. The applicability in the field of temperature sensing was explored based on the FIR approach, estimating SA as 2.562 \(\times\) 10–4 K−1 and SR as 0.02% K−1 at 473 K.
