| Abstract [eng] |
In this research, monophasic lithium aluminum germanium oxide LiAlGeO4 and impure lithium yttrium germanium oxide LiYGeO4 were synthesized using solid-state synthesis method by heating at 800°C for 6 hours and 6 hours 1050°C (900-1100°C for LiYGeO4) afterwards. LiAlGeO4: Bi and LiYGeO4: Bi samples were prepared to investigate the optical properties of LiAlGeO4 and compare them with LiYGeO4. A series of Eu3 + doped lithium aluminum germanates was also prepared to investigate the optical properties of LiAlGeO4: Eu. X-ray powder diffraction (XRD) and luminescence measurements were performed on the samples. LiYGeO4: Bi 1% couldn’t be synthesized pure while LiAlGeO4: Bi 1% was synthesized without any impurities. The highest Eu3 + concentration yielding monophasic samples in lithium aluminum germanate Li1Al1-xGeO4: Eu x, was x = 0.08. While comparing the luminescence studies of LiAlGeO4: Bi and LiYGeO4: Bi, it was found that the LiYGeO4: Bi sample has a more intense emission. LiAlGeO4: Eu luminescence studies revealed a higher emission of the 16% Eu sample. This sample also had the highest quantum efficiency of all the LiAlGeO4: Eu samples we tested. |
