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

Abstract GaN:Eu nanoparticles have been synthesized by simple ammonification of a mixture of Ga(NO 3 ) 3 and Eu(NO 3 ) 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 Ga N 6 bonds, respectively. From PL spectra, five characteristic peaks of Eu 3+ ions were clearly observed: 5 D 1  →  7 F 1 (543 nm), 5 D 0  →  7 F 1 (592 nm), 5 D 0  →  7 F 2 (614 nm), 5 D 0  →  7 F 3 (652 nm), 5 D 0  →  7 F 4 (697 nm). Besides, the influences of the synthesized temperature and Eu 3+ ion concentration on the PL behaviors were also studied.