SYNTHESIS, PHOTOLUMINESCENCE, AND APPLICATION POTENTIAL OF REDDISH-ORANGE EMITTING Eu3+ -DOPED BaSN PHOSPHOR

Abstract

Eu3+-activated reddish–orange phosphors, Ba3Sr(1−x)Nb2O9(Ba3SrNb2O9):xEu3+ (x = 1.0–9.0 mol%, Δx = 2 mol%), BaSN, were prepared using the conventional high-temperature solid-state method. The structural and phase analysis for all synthesized powdered samples, as examined by X-ray diffraction (XRD) patterns, align consistently with the JCPDS card no. 96-202-0162. Scanning electron microscopy (SEM) revealed micrometre-scale dimensions and irregular particles. The lattice vibrational of the BaSN host were characterized by the Fourier-transform infrared spectroscopy (FT-IR), while the calculation of the optical band gap was from the Diffuse Reflectance Spectra (DRS) using Tauc’s method. Photoluminescence (PL) excitation spectra and emission spectra, and decay lifetimes were deployed to characterise the optical and luminescence properties of the prepared samples. Upon near-UV excitation at 395 nm wavelength, the PL spectra exhibited intense reddish–orange emission, dominated by the (5D0→7F1,2) transitions of Eu3+, with the magnetic dipole transition of (7F1) being the most prominent. The PL emission intensity peaked at an Eu3+ ion concentration of 7.0 mol%, but subsequently decreased due to concentration quenching. Additionally, Colorimetric parameters, including CIE coordinates (x = 0.4672, y = 0.4991), color purity, and correlated color temperature (CCT), indicated favorable and optical performance of the doped and un-doped BaSN phosphor. The decay profiles exhibited a double-exponential behaviour, described by a decrease in lifetime values with increasing Eu3+ concentrations due to non-radiative transfer of energy between the dopant Eu3+ ions. Overall, these results demonstrate the potential of Eu3+-doped BaSN phosphors for the generation of solid-state lighting industry, specifically for near-UV-driven w-LED technology.