Ga₂O₃ nanomaterials synthesized from ball-milled GaN powders

Ga₂O₃ nanomaterials were synthesized from mechanically ground GaN powders with thermal annealing; Ga₂O₃ nanobelts were formed in a nitrogen atmosphere, while Ga₂O₃ nanoparticles were formed in an oxygen atmosphere. The structural properties of the Ga₂O₃ nanomaterials were investigated by X-ray diffractometer (XRD) and high-resolution transmission electron microscope (HRTEM). The study of field emission scanning electron microscopy (FESEM) on the microstructures of nanomaterials revealed that the nanobelts are in the range of about 10-200nm width and 10-50nm thickness, and that nanoparticles are in the range of about 20-50nm radius. On the basis of XRD and HRTEM data, we determined that the nanobelts grow toward a direction perpendicular to the (0 1 0) lattice plane and that they are enclosed by facets of the (1 0 1̄) and (1 0 1) lattice planes. The formation of the nanobelts may be described by the vapor-solid (VS) mechanism, and the supersaturation degree of gaseous phase may play an important role in the formation of Ga₂O₃ nanomaterials.