LAUSR

Abstract Ce-phosphate (CePO4) with a monazite structure has been synthesized via a precipitation method using parameters optimized for calcination time, calcination temperature, pH, precipitation time and variable Cerium (Ce3+) ratios vs the P. A suite of such samples has been extensively studied and structurally characterized by X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Raman (at 532, 632, and 785 nm excitation wavelengths) and ATR-FTIR (at 1064 nm excitation wavelengths) spectroscopies, and photoluminescence. SEM was used to analyze different Ce3+ ratios vs P (Ce:P) where Ce = 1 and P = 1, 2, 4, 8, 16, 32, 128, and 256. Photoluminescence (PL) properties were also investigated using the (2D3/2→2F5/2) and (2D3/2→2F5/2) emissions at 338 and 320 nm. Increasing Ce3+ ratios caused new products which underwent the following four changes: (1) microstructural changes from macroscale with increased uniform compaction to particles, revealed by SEM; (2) the formation of a substructure in addition to a monoclinic orthophosphate, revealed by both (Raman and IR) spectroscopy measurements; (3) crystallinity deterioration surface defects, revealed by spectroscopy and PL; (4) additional sub-morphologies revealed by both spectroscopy measurements; and (5) the effect Ce4+ on the luminescence Ce3+ was studied considering the Ce ratios.