Shape-controlled synthesis of monodispersed beta-gallium oxide crystals by a simple precipitation technique

Uniformly sized and monodispersed β-Ga2O3 crystalline micro-rods and ellipsoids have been successfully synthesized through a facile direct precipitation technique, respectively, using Ga(NO3)3 and NH4OH solution as starting materials. The as-prepared particles were characterized by XRD, FESEM equipped with EDS, TEM equipped with SAED, TG-DSC and Laser diffraction particle size analyzer, respectively. The results showed that the obtained β-Ga2O3 particles with a narrow particle size distribution were assembled with single crystalline β-Ga2O3 nano-sheets with the thickness of 100 nm. Furthermore, the reaction parameters including aging temperature, the molar concentration of Ga3+ and pH value had an essential effect on the morphology and size of the particles. Ostwald ripening and oriented attachment growth mechanism of the uniformly hierarchical β-Ga2O3 crystals were proposed. Finally, the target fabricated by using the as-prepared β-Ga2O3 particles as the raw materials exhibited a density as high as 6.01 g/cm3, showing potential applications in the high-quality thin film formed by magnetron sputtering for optoelectronic devices.