Structural and optical properties of GaN:Eu nanoparticles synthesized by simple ammonification method

GaN:Eu nanoparticles have been synthesized by simple ammonification of a mixture of Ga(NO3)3 and Eu(NO3)3. TEM images showed that the sizes of the particles were almost uniform, and the average grain sizes of the samples prepared at 850, 950, and 1050 °C were evaluated as 4.2 nm, 16.8 nm, and 24.3 nm, respectively. Except for conventional GaN Raman shifts, two extra peaks at 255 and 419 cm−1 observed in the Raman spectra could be attributed to the phonons activated by surface disorders or finite-size effects and vibration mode of N-rich octahedral GaN6 bonds, respectively. From PL spectra, five characteristic peaks of Eu3+ ions were clearly observed: 5D1 → 7F1 (543 nm), 5D0 → 7F1 (592 nm), 5D0 → 7F2 (614 nm), 5D0 → 7F3 (652 nm), 5D0 → 7F4 (697 nm). Besides, the influences of the synthesized temperature and Eu3+ ion concentration on the PL behaviors were also studied.

► GaN:Eu nano-particles were prepared by simple ammonification method.
► Two extra Raman peaks at 255 and 419 cm−1 were observed and explained.
► The red feature emission of Eu3+ ions has been obtained.
► The influences of the synthesized temperature and Eu3+ ion concentration on the PL behaviors were studied.