Thermal, vibrational and optical properties of PrLuO3 interlanthanides from hydrothermally-derived precursors.

PrLuO3 interlanthanides were prepared at temperatures ranging from 800 °C to 1600 °C using hydrothermally-derived precursors. The chemical reactions observed include the conversion and segregation of Pr(OH)3 and LuO(OH), respectively, into PrO2 and Lu2O3 cubic oxides below 1200 °C, followed by the production of a mixture of hexagonal P63/mmc and orthorhombic Pnma PrLuO3 phases at 1400 °C. Phase-pure orthorhombic PrLuO3 was obtained at 1600 °C, which was corroborated by Raman and micro far-infrared spectroscopic analyses. Photoluminescence, colorimetric and lifetime measurements were carried out in PrLuO3 samples. Dominant emission verified in samples calcined at 1400 °C corresponds to the hypersensitive 3P0 → 3F2 transition with a color purity of 97% (decay times of 12 μs and 3 μs), while emissions for the phase-pure samples correspond to the 3P0 → 3H6 and 3P0 → 3H5 transitions with a color purity of 94% (a single luminescence lifetime of 12 μs). The optical properties of PrLuO3 interlanthanides thereby suggest that they can be used as luminescent materials in both structural arrangements.