Structural and vibrational study of titanium Monophosphates Na0.5M0.25Ti2 (PO4)3 (M = Mn, Ni)

This work is a systematic study of titanium phosphates compounds Na0.5M0.25Ti2(PO4)3 (M = Mn, Ni), which are characterized by X-ray diffraction (XRD), IR spectrometry, Raman and scanning electron microscopy. Indeed, the crystalline structures of the two compounds were determined in the orthorhombic system, with space group Pmmm (Z = 4); the determined unit cell parameters are: a = 14.59Å, b = 13.31 Å, c = 2.6 Å for Na0.5Mn0.25Ti2(PO4)3, and a = 14.60 Å, b = 13.31 Å, c = 2.67Å for Na0.5Ni0.25Ti2(PO4)3. The structures, compared to that of Li0.5M0.25Ti2(PO4)3, are constructed from [TiO6] octahedra and [PO4] tetrahedra connected by sharing angles along the c axis. The cations M = Mn2+, Ni2+, are located in half of the antiprismatic infection sites and are ordered.

Hydrothermal Synthesis of Layered Titanium Phosphate Ti2O2H(PO4)[(NH4)2PO4]2 and Its Potential Application in Cosmetics

Titanium phosphates were recently revealed as promising cosmetic pigments; however, their photocatalytic activity and sun protective factor (SPF) levels have not been investigated in detail. In this study, we used hydrothermal conditions to prepare nanocrystalline anatase, brookite, and layered titanium phosphate using the titanium lactate complex, NH4H2PO4, and urea as precursors. The samples were characterized by powder X-ray diffraction (XRD) in addition to Raman spectroscopy, transmission and scanning electron microscopy (TEM, SEM), energy-dispersive X-ray spectroscopy (EDX), and UV-Vis spectroscopy. Furthermore, the photocatalytic activity, sun protective factor, and moisture retention ability were determined for the samples. Brookite exhibited the highest SPF value and anatase the lowest, while Ti2O2H(PO4)[(NH4)2PO4]2 displayed highly promising UV protection and moisture retention properties and, therefore, represents a polyfunctional pigment that is particularly well suited for cosmetic applications.