Sol-gel combustion synthesis of high-quality chromium-doped mixed-metal garnets Y3Ga5O12 and Gd3Sc2Ga3O12

Characterization of GAGG Doped with Extremely Low Levels of Chromium and Exhibiting Exceptional Intensity of Emission in NIR Region

“…Such a shift to the red region was previously explained by the re-absorption of Cr 3+ ions [43]. Studies by other researchers revealed that a high photoluminescence intensity of chromium ions emission was only recorded with 2000 times higher amounts (for example, 3 mol%) of Cr 3+ in other compounds [44].…”

“…The absorption band at 360 and 440 nm is classified as a Ce 3+ electronic transition. In addition, there is no bright absorption band at 600 nm, which is typically observed in Cr 3+ -containing compounds [44,[46][47][48]. Figure 4 shows the reflectance spectra of the compounds.…”

“…The compounds appear to exhibit cerium-specific fluorescence at a wavelength of 540 nm, which arises from the 5d 1 to 4f 1 electronic transitions. Meanwhile, when investigating the excitation spectra of the compounds in addition to those cerium bands, the peaks contributing to gadolinium ions were observed in the 250-320 nm range [19,44]. Figure 4 shows the reflectance spectra of the compounds.…”

“…The absorption band at 360 and 440 nm is classified as a Ce 3+ electronic transition. In addition, there is no bright absorption band at 600 nm, which is typically observed in Cr 3+ -containing compounds [44,[46][47][48]. To better investigate the absorption of garnets in the UV region, the reflectance spectra of the synthesized gadolinium aluminum gallium garnets powders in the 130-400 nm range were recorded.…”

Ferromagnetic-like behavior of Bi0.9La0.1FeO3–KBr nanocomposites

“…Characteristic size of the grains attributed to KBr phase is in the range of 0.100 -10 µm. The crystallines ascribed to the ferrite phase are characterized by rectangular-shaped form, ferrite grains are mainly agglomerated into clusters having size of about 1-2 microns, while separate grains are characterized by nanometer size as confirmed by SEM images obtained for the composites and the single phase ferrite [compare The modified sol-gel method synthesis method and preparation conditions [28,29] used to synthesize nanoscale powder of Bi 1-x La x FeO 3 (x =0, 0.05, 0.1) lead to a formation of single phase stoichiometric ferrites utilized to form the composites. The X-ray diffraction measurements performed for the ferrite compounds have confirmed their single phase rhombohedral structure, the XRD patterns recorded at RT have been successfully refined assuming non-centrosymmetric rhombohedral space group R3c.…”