Investigating multipurpose reddish-orange emitting vanadate-based nanomaterials activated by Sm(III) for use in latent fingerprinting and photophysical applications

Abstract

Here, we report the synthesis of Sm³⁺- activated Ca₈ZnBi(VO₄)₇ nanophosphors using the easy, economic, and time-saving urea-aided solution combustion method. The fabricated powder samples that were annealed at 900 °C were examined for their structural, morphological, and optical characteristics. By recording the X-ray diffraction pattern, R3c (161), the space group and the trigonal phase of synthesized phosphor, was verified. Using X-ray energy-dispersive spectroscopy and scanning electron microscopy, the morphology and elemental composition of the phosphors were examined. Using a transmission electron microscope (TEM), the fabricated nanophosphor particle size was examined. A TEM image demonstrates the occurrence of uneven particle agglomeration in the nanoscale range. The synthesized phosphors’ excitation, emission spectra were captured to examine their photoluminescence (PL) behavior. We observed characteristic reddish-orange Sm³⁺ PL emission when the produced Ca₈ZnBi (VO₄)₇ phosphors material was exposed to UV light at 408 nm, this corresponded to the transition ⁴G_5/2 → ⁶H_7/2, at 605 nm, respectively. Dexter’s theory and the Inokuti–Hirayama (I–H) model were used to confirm that the energy migration among neighbor ions is found to be responsible for concentration quenching and 5 mol % is found to be the optimal concentration of dopant ion. Using the diffuse reflectance (DR) spectrum, the Eg (bandgap) values for Ca₈ZnBi(VO₄)₇ (3.18 eV) and Ca₈ZnBi_0.95Sm_0.05(VO₄)₇ (3.15 eV) were determined. In addition, a detailed evaluation was conducted on the quantum efficiency (64.74 %), radiative lifetime (0.6329 ms), and color coordinates (0.6522,0.3476). These astounding outcomes demonstrated the synthesized nanomaterials suitability for creating wLEDs, inherent fingerprinting, and other photophysical claims.