Synthesis and characterization of Ce-doped HfO2 nanoparticles in molten chlorides

Ce-doped HfO2 nanoparticles were successfully prepared in molten chlorides. Nanoparticles were obtained at 380 °C during 1 h in a LiCl/KCl molten flux. The Ce-doped HfO2 nanoparticles showed sizes below 7 nm and spherical shapes. Complete stabilization of cubic phase was achieved by adding 10 mol % of Ce. XRD, Raman and HRTEM techniques confirmed that the Ce-doped HfO2 nanoparticles have a cubic structure. Furthermore, this simple, efficient and high yield (>95%) method represents an alternative route for the synthesis of fluorite-type cubic phases and should be useful for doping or co-doping HfO2 with other cations.