Study of structural and optical properties of europium ion activated bismuth oxide nanophosphors

Abstract

The current study examines the structural and optical features of un-doped and a series of Eu3+ ion-doped bismuth oxide nanophosphors synthesized via a facile, low-cost, and room temperature co-precipitation route. X-ray diffraction (XRD) analysis confirms the monoclinic crystal structure without any trace of impurity. The FTIR spectroscopic analysis of the samples has been taken in 400–4000 cm−1 wavenumber range to analyze the bonding states and functional groups of the species. Optical properties of the samples have been investigated using UV–Vis and photoluminescence (PL) spectroscopy. We observed a slight increase in the band gap in the doped samples (2.79–2.81 eV) as compared to the bismuth oxide host (2.77 eV). The photoluminescence emission studies have been carried out under 466 nm excitation wavelength over the range of 550–750 nm. The most prominent peak in the emission spectra is observed at 612 nm corresponding to(5D0 → 7F2)transition of Eu3+ ion. An explicit augmentation in the emission intensity is observed in 7 mol% Eu3+ doped Bi2O3 nanophosphor. The emission spectra were used to calculate the CIE chromaticity coordinates and CCT of the phosphors. The CIE coordinates depict an evident red-shift in the Eu3+ doped phosphors. The CCT values have been sufficiently alleviated after Eu3+ doping. Thus, our study corroborates an evident red-shift in the aforementioned optimized composition and suggests that it is a potential candidate for lighting and display devices.