Luminescence and structural properties of europium doped titania in the 600–750 °C range

Abstract

In this study, europium doped titania nanophosphors are synthetized and characterize in order to understand the relationship between structural changes induced by heat treatments and luminescence properties. After heat treatments, phase changes are observed between 600 °C and 700 °C and characterized using X-ray diffraction and Raman spectroscopy. These phase changes include the anatase – rutile transition and the apparition of secondary phases such as europium oxide and pyrochlore phase (Eu2Ti2O7). Along with the phase changes and crystallite size evolution, the luminescence intensity of the 5D0→ 7F2 transition and the lifetime decay are measured after green laser excitation (532 nm). The europium concentration is a key parameter to obtain a monotone and bijective relationship between the temperature and the luminescence behavior.