Photoluminescent and X-ray photoemission studies of Eu3+-doped kosnarite KZr2(PO4)3 nanophosphor and its Judd–Ofelt analysis

K Zr 2 PO 4 3 : xEu 3 + Nanophosphors with varying molar percentages (0.5, 1, 2, 3, 4, and 5 mol. %) are synthesized using a urea-assisted solution combustion synthesis approach. The phosphors exhibit crystallization in a rhombohedral phase, namely in the R 3 ¯ c space group with the help of X-ray diffraction. The anionic group of (PO 4 ) 3− is responsible for all the vibrations occurring in the FTIR spectra. The photoluminescence characteristics of K Zr 2 PO 4 3 : xEu 3 + ( x = 0.5 – 5 mol. %) are examined when excited at a wavelength of 392 nm, resulting in the prominent emission at 613 nm. At a concentration of 2 mol. %, the optimal concentration is observed, and the emission tone of the phosphor is centered in the reddish part of the color gamut, with a high color purity of 92%. It is observed that the synthesized phosphor has a branching ratio more than 50%, indicating a possible laser emission transition. The band gap energy of K Zr 2 PO 4 3 : Eu 3 + is found via diffuse reflectance measurements and found to be 4.19 eV. The value of metallization criteria is less than unity which dictates the non-metallic nature of the synthesized phosphors. These results indicate that this phosphor is very suitable for use in solid-state lighting applications as a red light-emitting phosphor.