Novel monazite type rare earth based phosphates ARP3O10 (A=Ba or Ca; R=La, Ce or Sm) - Studies on their preparation, structure, microstructure and dielectric properties

This paper presents the results of the investigations carried out on the preparation, structure and properties of certain novel rare earth based phosphate compounds such as BaSmP3O10, CaSmP3O10, BaCeP3O10, CaCeP3O10, BaLaP3O10, and CaCeP3O10. The phase identification of these phosphates is done by powder X-ray diffraction (XRD) which clearly shows the formation of monoclinic monazite type structure. The grain morphology of the compounds is studied by Scanning Electron Microscope (SEM). All the compounds except BaLaP3O10 show well-grown grains. BaLaP3O10 is unstable when kept in air for a few days. Dielectric properties of all the new phosphates have been measured as a function of frequency at room temperature. It is seen that these new rare earth phosphates have low dielectric constant and moderate dissipation factor.