Transparent high entropy garnet ceramics by SPS

Abstract

High entropy or multi-principles component oxides as a new class of materials have been widely investigated for various applications due to their unique properties and multi-functionalities in recent years. In this study, a high entropy transparent ceramics ((Gd0.2Tb0.2Y0.2Lu0.2Yb0.2)3Al5O12) has been fabricated by spark plasma sintering (SPS) using co-precipitation synthesized powders. The powder preparation process was studied by TAG-DSC and FTIR. The phase structure, morphology, and element distribution of the obtained powder and ceramic samples are explored by XRD, SEM, and EDS mapping. It shows that the high entropy oxide (HEO) ceramic powder has a pure garnet phase, nanoparticle size, and homogenous elements distribution. The sintered ceramic exhibits the highest in-line transmittance in the visible and IR range of approximately 52 % at 700 nm and 74 % at 3.6 μm, respectively. In addition, characteristic optical properties of the final ceramics were demonstrated by photoluminescence spectroscopy. This work indicated that high-entropy garnet transparent ceramics with multi-wavelength emissions will provide more possibilities for multifunctional optical applications in the future.