Partial wet route for YAG powders synthesis leading to transparent ceramic: A core–shell solid-state reaction process

Abstract

Abstract Synthesis of Y 3 Al 5 O 12 (YAG) powders respectively presents morphology control and chemical stoichiometry problems when employing the solid-state reaction or the wet-chemical route. YAG powder retaining the morphology of Al 2 O 3 powder was designed and synthesized via a partial wet-chemical process with yttrium ions precipitating on the Al 2 O 3 particles. The formation process of the Y-compound/Al 2 O 3 core–shell structure is discussed on the basis of zeta-potential measurements and HRTEM results. Two stages, including direct precipitation at the surface of the Al 2 O 3 particles and the assembly of the yttrium precipitate from explosive nucleation onto the yttrium compound-coated Al 2 O 3 particles, are proposed. A spherical surface reaction process is illustrated. A pure YAG phase can be realized at a temperature about 300 °C lower than that of the traditional solid-state reaction process.