SYNTHESIS OF CERIA NANOPARTICLES: EFFECT OF ALCOHOL/WATER RATIO ON THE MORPHOLOGY AND CRYSTAL STRUCTURE

Abstract

In this study, ceria nanoparticles were synthesized via one of the simplest methods, which is the precipitation method. The effects of three different ethanol/DI water ratios (i.e. 1:1; 1:4; 0:1) and post-heat treatments (i.e. drying only and drying + calcination) on the crystal structure and morphology of the ceria nanoparticles have been investigated. The characterization of the ceria nanoparticles was conducted using X-Ray Diffractometer (XRD) for the crystal structure and Transmission Electron Microscopy (TEM) for the morphology. From XRD analysis results, the comparison of the highest XRD intensity peaks (at 2θ = 28.6°) of the ceria nanoparticles samples showed that all the ceria nanoparticles samples with drying + calcination treatment were higher than the ones with drying treatment only. Additionally, the XRD peaks were analyzed using a well-known Scherrer’s equation to determine the average crystallite size of the ceria nanoparticles. It was found that the ceria nanoparticles sample prepared using the ethanol/DI water ratio of 1:1 (i.e. Ceria-C1) had the biggest average crystallite size (i.e. 14 nm). Nevertheless, the TEM analysis showed that Ceria-C1 showed better morphology and dispersion compared to other Ceria samples and also clearly exhibited sphere-like nanoparticles. This finding can be associated with the dispersion stability analysis, which showed that the suspension of Ceria-C1 shows a little bit better dispersion compared to other Ceria samples.