Perovskite SrZrO₃:Ho³⁺ phosphors: synthesis, structure, Judd-Ofelt analysis and photoluminescence properties

A series of SrZrO₃:xHo³⁺ (x = 0.01, 0.03, 0.05, 0.07, 0.09, and 0.11 mol) perovskite phosphors have been synthesized by using the sol-gel technique. The structural and optical characteristics of the prepared phosphors have been investigated through powder XRD, FT-IR, UV-visible diffuse reflectance, and photoluminescence analysis. The photoluminescence emission spectra showed a bright characteristic peak at 545 nm (⁵F₄ + ⁵S₂ → ⁵I₈) under the 454 nm excitation, which exhibits emission in the green region of the electromagnetic spectrum. The emission intensity of the phosphors starts decreasing slowly beyond 3 mol% Ho³⁺ ions concentration due to concentration quenching, which is attributed to the dipole-dipole interaction between Ho³⁺ ions. The site symmetry of the Ho³⁺ ions has been studied by estimating the relative Judd-Ofelt intensity parameters (Ω, where λ = 2, 4, 6) from the photoluminescence excitation spectrum of the SrZrO₃:0.03Ho³⁺ phosphor. The obtained findings suggest that the synthesized phosphors will be favorable for their bright green emission and thus, can be widely used for different optoelectronic applications.