Influence of Various Surfactants on Size, Morphology, and Optical Properties of CeO2 Nanostructures via Facile Hydrothermal Route

Different surfactants such as sodium dodecyl sulfate (SDS), polyethylene glycol (PEG), and cetyltrimethyl ammonium bromide (CTAB,) assisted cerium oxide (CeO2) nanoparticles were synthesized by using cerium chloride and potassium hydroxide as the starting materials via facile hydrothermal route. The powder X-ray diffraction (XRD) shows that cubic fluorite-type structure of pure CeO2 and the average crystallite sizes were calculated to be ~12–16 nm. Raman spectra of various surfactants assisted CeO2 consist of a single triply degenerated F2g mode characteristic of the fluorite structure. The elongated spherical-like morphology of SDS assisted CeO2 samples was observed from the SEM and TEM studies. Optical absorption spectra showed a blue shift by the capped CeO2 due to the quantum confinement effect. Photoluminescence (PL) emission studies shows that there is a change in the intensity of emission peaks by the capping agents, which indicates that the capping layers did result in size changes or increased surface defect.