Garnet transparent ceramic film of Y3Al5O12:Eu3+ fabricated through an interface reaction of layered rare-earth hydroxide nanosheets on amorphous alumina

Traditional preparation of yttrium aluminum garnet (YAG) transparent ceramics involves the steps of powder preparation, green body formation and sintering. It is not only time-consuming, high energy consumption and high cost, but also has high requirements for equipment. Here, we developed a special interface reaction to prepare YAG transparent ceramic film. Transparent ceramic fluorescent film composed of YAG: Eu3+ was prepared by spin-coating the exfoliated layered rare earth hydroxide (LRH) nanosheets on the amorphous alumina substrate, followed by sintering at 1500 degrees C for 2 h in air. Al element tends to diffusion to the rare earth oxide side for the interface reaction, and more Al participates in the reaction at a higher temperature. The higher temperature makes more amorphous Al2O3 gradually participate in the interface reaction, and react with (Y0.95Eu0.05)2O3 to form mesophases of (Y0.95Eu0.05)4Al2O9 and (Y0.95Eu0.05)AlO3 at temperature lower than 1500 degrees C, and finally to form (Y0.95Eu0.05)3Al5O12 (YAG: Eu3+) at 1500 degrees C. The fluorescent film exhibited red emission at 618 nm, which is different from the orange red emission for YAG: Eu3+. The red emission at 150 degrees C maintained over 85% intensity of that at room temperature. We believe that the outcomes of this work may enrich the applications of the LRH nanosheets and may have wide implications to other compositional transparent ceramics.

Automated summary

The traditional preparation of YAG transparent ceramics is time-consuming and costly, with high energy consumption and equipment requirements. A special interface reaction method was developed in this study to prepare YAG transparent ceramic films with unique fluorescent properties, which may have broad applications in the field of transparent ceramics.