Microwave Hydrothermal Preparation And Photocatalytic Performance Of Nano-?, ?- And ?-Ga 2 O 3

Photocatalytic technology is a new technology of modern environmental pollution control.As a photocatalyst,Ga₂O₃ has many advantages,such as non-toxic,low cost,stable performance and high catalytic activity.It has a broad application prospect in the treatment of environment pollutants.In this paper,Ga?NO₃?₃ was used as the gallium source and urea was the precipitant.Under microwave heating conditions,the rod GaOOH and ultrafine spherical?-Ga₂O₃ nanoparticles can be synthesized by adjusting the temperature of microwave heating,the time of heat preservation and the amount of urea.The rod?-Ga₂O₃ and?-Ga₂O₃ were prepared by calcining GaOOH at 500 and700?,respectively.When calcining ultrafine?-Ga₂O₃ at 500?,the sample was still remained pure phase?-Ga2O3 with the highest crystallinity.When the calcination temperature rose to 700?,the products were all transformed into spherical?-Ga₂O₃.Photocatalytic activity of the catalysts were tested by UV photocatalytic degradation of RhB.The photocatalytic degradation rates of RhB by catalysts are as follow:spherical?-Ga₂O₃?95.5%?>rod?-Ga₂O₃?91.7%?>500?-?-Ga₂O₃?90.7%?>?-Ga₂O₃?75.8%?>ultrafine?-Ga₂O₃?68.2%?>GaOOH?32.9%?.Comparison of photocatalytic degradation result of commercial TiO₂?P25?to RhB?79.4%?,the samples after calcination have certain advantages in photocatalysis.Especially spherical?-Ga₂O₃ prepared by calcining the?-Ga₂O₃ precursor has the highest photocatalytic activity.