Synthesis of polycrystalline yttrium iron garnet and yttrium aluminium garnet from organic precursors

Abstract

Polycrystalline Y3FesO~2 (YIG) and Y3AIsO~2 (YAG) garnets have been prepared by the organic solution technique using a novel organic precursor. The thermal decomposition of the precursor and subsequent formation of the garnet phases was studied by thermal analysis, X-ray diffraction and Fourier transform infra red spectroscopy (FTIR) including diffuse reflectance FTIR (DRIFT). The precursor of YIG decomposes to give the garnet phase as the main component at 800 ~ YFeO 3 and Fe203 are also present, and react to give YIG at higher temperatures. Single-phase YAG can be obtained from its precursor at 11 O0 ~ The reaction proceeds via a hexagonal YAI03 intermediate which is formed at 850 ~

Magnetic and FTIR studies of BixY3−xFe5O12 (x=0, 1, 2) powders prepared by the metal organic decomposition method

“…The remaining YFO phases may be due to insufficient sintering time or chemical inhomogeneity caused by decomposition of the organic parts. The appearance and crystallization temperature of the garnet phase was similar to other preparation methods [12][13][14].…”

Preparation of bismuth substituted yttrium iron garnet powder and thin film by the metal-organic decomposition method

“…Interestingly, the sample directly annealed at 750 1C without pre-annealing and the sample pre-annealed at 400 1C with the post-annealing process were light yellow in color but samples preannealed at 500-700 1C with the post-annealing process were tan yellow. This change can be thought as an attribute of the secondary phases, YFeO 3 and a-Fe 2 O 3 , which are red due to strong absorption in the blue region [34]. Fig.…”

Influence of the co-precipitation temperature on phase evolution in yttrium-aluminium oxide materials

“…Although a lot of investigations on pure alumina preparation have underlined the strong influence of some process parameters (temperature, pH, rate of addition and nature of the precipitation agent) [8][9][10][11][12] on the phase evolution and on the properties of the synthesized alumina, when wet chemical syntheses and particularly precipitation are used, similar studies on pure YAG are lacking in the literature, even if many have been recently addressed to the synthesis features. [13][14][15][16][17][18][19][20] In this work YAG powders have been synthesized by using reverse-strike precipitation 6,7,14,[17][18][19][20] (i.e., adding an aqueous Y and Al salts solution to the precipitant solution) which has the advantage to assure a higher cations homogeneity in the precipitate precursor in the case of multi-cation materials. 20 The influence of the final pH value cannot be significantly investigated since a complete precipitation of both Y and Al hydroxides is reached at pH of around 9.…”