Green Emission in Thermally Stable Er³⁺ Doped Lead-Free Perovskite Phosphor for Solid-State Lighting and Optical Thermometry Applications

Abstract

CaTiO 3 :xEr 3+ (0.1≤x≤7 mole %) phosphor materials were meticulously prepared through the solution combustion method. Comprehensive analyses employing Powder X-ray Diffraction (PXRD), Field Emission Scanning Electron Microscopy (FESEM), and Fourier Transform Infrared Spectroscopy (FTIR) were conducted to investigate the phase, morphology, and vibrational characteristics of the synthesized phosphors. A detailed luminescence study was undertaken using photoluminescence spectroscopy, revealing distinctive 4f-4f transitions associated with Er 3+ in both excitation and emission spectra. The application of Dexter's theory provided insights into the quenching mechanism inherent in CaTiO 3 :Er 3+ phosphors. Photometric studies were carried out to evaluate the suitability of the synthesized material for solid-state lighting applications. Furthermore, to assess the thermal stability of the phosphor material, the activation energy was computed. The fluorescence intensity ratio of thermally coupled energy levels of Er 3+ ion was utilized to assess the temperature-sensing capabilities of the synthesized material. This material may be suitable for solidstate lighting and optical thermometry applications. Index terms-Perovskite, Phosphor, solid-state lighting, and optical thermometry.