Luminescence efficiency of cerium-doped yttrium aluminum garnet ceramics formed by radiation assisted synthesis

Abstract

The variety of applications of yttrium-aluminum garnet (YAG)-based luminescent materials and the morphology necessary for these purposes required the development of many technologies for their synthesis. All synthesis technologies used are complex. The structural phase of yttrium-aluminum garnet is formed with any technology, at temperatures exceeding 1,500 °C. The starting materials for the synthesis are metal oxides of aluminum, yttrium and other oxides for activation and modification. It seems possible to use hard radiation to form a new phase. Radiation synthesis of ceramics is realized in less than 1 s, without the use of any additives and influences. The synthesis was carried out at the electron accelerator of the Institute of Nuclear Physics (Novosibirsk). In this work, we studied the spectral-kinetic and quantitative characteristics of luminescence for the first time obtained by the method of radiation synthesis of ceramic samples of yttrium-aluminum garnet doped with cerium with statistical processing of their values. The dependences of the reproducibility of the spectral characteristics of the luminescence of the samples on the preliminary preparation of the charge for synthesis have been investigated. Several cycles of luminophore brightness studies have been performed. It is shown that the obtained ceramics based on yttrium-aluminum garnet doped with cerium possesses the required spectral-kinetic properties, and the efficiency of conversion of the chip radiation into luminescence is achieved, which is comparable to that available in commercial phosphors. The maximum measured values of the position of the bands are from 553.5 to 559.6 nm. Brightness values range from 4,720 to 1,960 cd/m2. It was found that the main reason for the scatter in the characteristics of the luminescent properties of ceramics of yttrium-aluminum garnet, activated by cerium obtained by radiation assisted synthesis is the high rate of synthesis and, especially, the high rate of cooling of the samples.

Express Synthesis of YAG:Ce Ceramics in the High-Energy Electrons Flow Field

“…Essential for the synthesized luminescent ceramics is a quantitative characteristic, the efficiency of the conversion of the excitation energy Φ ex into luminescence Φ em : η = Φ em /Φ ex The quantitative measurements of the optical radiation are complex: the measurement result depends on the luminescence and excitation spectra and light distribution in space. For operational quantitative measurements, it is possible to use methods for comparing luminescence brightness’ [ 25 ]. The luminescence brightness of diffusely scattering media, which are powders, is proportional to the radiation flux.…”

Study of β-Ga2O3 Ceramics Synthesized under Powerful Electron Beam

“…In addition to the previously discussed techniques, recent studies have unveiled impressive results on the fabrication of refractory ceramics, specifically magnesium fluoride (MgF 2 ) and yttrium-aluminum garnet (YAG) ceramics, utilizing a powerful electron beam [33][34][35]. Consequently, there is a heightened interest in the development and refinement of this newly proposed synthesis method for refractory materials employing a powerful electron beam.…”