Structural and luminescent properties of Eu3+ doped multi-principal component Ce0.2Gd0.2Hf0.2La0.2Zr0.2O2 nanoparticles

We report the luminescent properties and local structural studies of multi-principal component Ce0.2Gd0.2Hf0.2La0.2Zr0.2O2 oxide nanoparticles using Eu3+ as a luminescent dopant. A simple chemical co-precipitation of metal salts accompanied by peptization in an acidic medium was carried out to obtain various compositions of Eu3+-doped Ce0.2Gd0.2Hf0.2La0.2Zr0.2O2 nanoparticle sols. The sols were dried in an oven at 110 °C for 24 h, and the resultant powder was calcined in static air for 2 h at 500 °C, 750 °C, and 1000 °C. The calcined nanoparticles were characterized by using x-ray diffraction (XRD), UV–Visible spectroscopy (UV–Vis), and Photoluminescence spectroscopy (PL). All the calcined Eu3+-doped samples revealed a single-phase cubic fluorite solid solution without any phase separation. PL studies on various concentrations of Eu3+ doping and calcination temperatures have been evaluated. The Eu3+ emission features are excitation wavelength-dependent. In addition, PL emission intensity increased with increasing Eu3+ concentration and calcination temperatures. The luminescent properties of these multi-principal component oxides were associated with its local environment based on the location of Eu3+ inside the host lattice. The asymmetric ratios calculated from the emission spectrum provided an insight into the local environment around the Eu3+ ion and confirmed that the system contains disordered defects even when heat treated at higher temperatures showing a stable defect fluorite structure. The reported Eu3+ doped Ce0.2Gd0.2Hf0.2La0.2Zr0.2O2 nanoparticles will be a suitable candidate for imaging as well as in lighting applications.