Controlled Synthesis of GaN@SiO₂ Particles in Preventing the Hydrolysis of GaN

Abstract

GaN small particles are sensitive to water molecules and easily hydrolyzed into GaOOH when exposed to atmosphere. One of the perfect solutions is to coat them with SiO 2, which serves as a protective layer against adsorption of water molecules on the GaN surface and effectively prevents the hydrolysis of GaN. Herein, the synthesis of GaN@SiO 2 with morphologies of microrhombuses and microrods is demonstrated. The products of GaN@SiO 2 were characterized by XRD, indicating that there was almost no hydrolysis of GaN@SiO 2 after one year exposition in the air. The photoluminescence (PL) of GaN microrhombuses and microrods exhibited emission peaks in the blue region, as did the GaN@SiO 2 products. The luminescence intensity increased after SiO 2 coating, while the PL position was not shifted. The silica shell effectively prevented the hydrolysis of GaN and successfully preserved the luminescence properties of GaN microrhombuses and microrods.