Pr-Activated SrLaF Nanoparticles as a Single-Phase White-Light-Emitting Nanophosphor.

SrLaF:Pr ( = 0.2, 1, 2, 3, 5, 10, and 25 mol%) nanophosphors with a cubic Fm3m structure were hydrothermally synthesized, forming nearly spherical nanoparticles with an average diameter of approximately 32 nm. Diffuse reflectance measurement and excitation spectra showed a primary excitation peak of Pr at 443 nm, corresponding to the ground state to the P level transition. Upon blue light excitation, Pr-activated SrLaF nanophosphors showed rich emission structure across the visible region of the spectrum, with blue (483 nm), green (525 nm), orange (600 nm), and red (640 nm) emissions, blue and orange being the most prominent ones. The relative intensities of these emissions varied with Pr concentration, leading to tunable emission colors. The chromaticity showed slight variation with the Pr content (0.350 < x < 0.417, 0.374 < y < 0.380), while the CCT value increased from 3118 K to 4901 K as the doping concentration increased. The optimized SrLaF with 2 mol% Pr had the most intense emission with correlated color temperature (CCT) of 3628 K, corresponding to the warm white color. The proposed Pr-doping strategy offers valuable insights into discovering or optimizing single-phase phosphors for white-light-emitting applications.