Electrochemical and structural analysis of the RE³⁺:CeO₂ nanopowders from combustion synthesis

Highlights: • Rare earth elements doped ceria were synthesized by citrate nitrate auto-combustion method. • XRD revealed that they crystallize as single-phase cubic fluorite structure. • PL, FTIR and RAMAN studies were carried to analyze the existence of functional groups. • The morphology of the nanoparticles and compacts were analyzed by SEM and HRTEM. • Cyclic voltammetry (CV) for RE³⁺:CeO₂ were measured and compared. - Abstract: The reported article deals with the synthesis and characterization of rare earth ions doped ceria (RE³⁺:CeO₂) nanopowders from citrate nitrate auto-combustion route. The crystalline nature and lattice planes of the nanocrystalline RE³⁺:CeO₂ powders were analyzed by X-ray diffraction (XRD) and Selected Area Electron Diffraction (SAED) profile fit. The excited state absorption (ESA) and energy transfer up-conversion (ETU) were studied by photoluminescence (PL) measurement. The spectroscopic properties of the powders were studied using Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy. The surface morphology, average size, distribution and orientation of the lattice planes of the nanoparticles were studied by using scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM). The size of RE³⁺:CeO₂ nanoparticles were found to be in the range from 15 to 30 nm which has good agreement with the HRTEM results. The changes in current density with increasing sweep scan potential of the doped ceria powders were studied by cyclic voltammetry (CV) analysis. The specific capacitance range of the rare earths doped ceria of Er:CeO₂, Pr:CeO₂, Yr:CeO₂ and Nd:CeO₂ were calculated as (12.9–86.5), (20–72.4), (80–375) and (0.92–4.22) respectively