Spectral and trapping parameters of Eu3+ in Gd2O2S nanophosphor

This paper reports the structural, photometric, spectral and trapping parameters of Eu³⁺-doped gadolinium oxysulphide nanophosphor. The X-ray diffraction (XRD) data show the presence of the hexagonal phase of Gd₂O₂S and a crystallite size in nanometre range. Different structural parameters were calculated from XRD data. The Fourier transform infrared (FTIR) spectrum also confirms the formation of a compound. Scanning electron microscope studies reveal the morphology and crystallite size of the prepared phosphor. The band gap of the phosphor was calculated from diffuse reflectance spectra using the Kubelka–Munk function at 4.76 eV. The phosphor was illuminated with ultraviolet light and shows the characteristic red luminescence corresponding to ⁵D₀→⁷F_J transitions of Eu³⁺. The Judd–Ofelt intensity parameters and spectral parameters were estimated from the photoluminescence data. The nanophosphor was irradiated with γ-rays in the dose range 15–50 Gy for thermoluminescence (TL) studies and a shifting of the peak towards lower temperatures was observed with increasing γ-dose. Trapping parameters were calculated from TL data using various glow curve analysis methods.