Structural, optical and luminescence properties of BaLaGa3O7: x Eu3+ ceramic phosphors

Abstract

The undoped and Eu3+ doped BaLaGa3O7 ceramic phosphors have been prepared using solid state reaction technique. The structural studies have been done using X-ray Diffraction (XRD) and Fourier transform infra-red (FTIR) technique and the surface morphology analysis using Field emission scanning electron microscope (FESEM). The elemental analysis has been carried out using Energy Dispersive X-ray spectroscopy (EDX) and elemental mapping. XRD study reveals that all the prepared phosphors are single phase with tetragonal crystal structure. The FESEM and EDX spectra confirm the single phase nature of the phosphors. FTIR technique identifies the various vibrational modes present in the prepared phosphors. The UV–Visible analysis provides the absorption region and band gap energies of undoped as well as doped BaLaGa3O7 phosphors. The photoluminescence (PL) excitation spectra consist of sharp excitation peaks of Eu3+ ions at 374 and 394 nm. The emission spectra corresponding to excitation wavelengths of 374 and 394 nm have been carried out. Maximum PL emission is obtained for excitation at 374 nm and it provides excellent orange red emission. The decay profile of BaLaGa3O7:xEu3+ phosphors have been carried out. The mechanoluminescence (ML) property of the doped phosphors reveals good ML emission without any pre irradiation. The information about the trap depth parameters and charge carriers in the 1 kGy irradiated BaLaGa3O7 phosphor has been studied using the thermoluminescence (TL) glow curves. The BaLaGa3O7 phosphor is having kinetics of first order with activation energy 1.107 eV.