Noticeable red emission and Raman active modes in nanoscale gadolinium oxyfluoride (Gd4O3F6) systems with Eu3+ inclusion

Abstract

Eu3+ doped gadolinium oxyfluoride (Gd4O3F6, GOF) nanoscale systems have been synthesized following a modified Pechini method. While exhibiting a tetragonal crystal structure, the GOF nanosystem gave an average crystallite size (d) of ~21–26 nm. The Lotgering factor (LF), which is a measure of orientation of crystallites along the preferred direction was found to vary between 0.22 and 0.48. In the photoluminescence spectra, ~595 and ~613 nm peaks were identified as magnetically driven (5D0 → 7F1) and electrically driven (5D0 → 7F2) transitions with latter (red emission) being strongly manifested with Eu3+ doping concentration and intrinsic defects. Moreover, several Raman active modes have been probed in the Raman spectra with low frequency peaks (<300 cm−1) and moderate frequency peaks (~481 and 567 cm−1) assigned to observable vibration of heavy atom Gd–Gd pairs and Gd–O groups, respectively. Apart from manifestation of phononic features, inclusion of Eu3+ in the host lattice would bring new insight on improving the red emission response prior to concentration quenching.