Synthesis and Characterization of Plate-Like Cerium Phosphate via Soft Solution Processing
Because of the low refractive indices, plate-like cerium phosphates (CePs) are expected to be used as one of active ingredients in personal suncare cosmetics. Plate-like Ce2(PO4)2HPO4･H2O particles were synthesized via solvothermal reactions of Ce(NH4)2(NO3)6 or Ce(SO4)2･4H2O in phosphoric acid with or without nitric acid and sulfuric acid solutions. The variation of morphology of Ce2(PO4)2HPO4･H2O particles significantly depended on the variety of cerium salt, isothermal temperature and time, although all reaction products consisted of plate-like particles. This plate-like compound showed excellent UV light absorption and transparency in the visible light region. Consequently, it is suggested that the plate-like Ce2(PO4)2HPO4･H2O particles might be used as suncare products to give an ideal optical effect of both UV-shielding ability and transparency in the visible light region, as well as a good feeling on the skin.
R. X. Li et al., "Synthesis and Characterization of Plate-Like Cerium Phosphate via Soft Solution Processing", Advances in Science and Technology, Vol. 45, pp. 668-672, 2006