Controllable fabrication of Bi₂O₃ nanoparticles by atomic layer deposition on TiO₂ films and application in photodegradation

Bi₂O₃ nanoparticles prepared by atomic layer deposition (ALD) are growth on TiO₂ films. As catalyst, It is found that the photocatalytic effective is associated with the cycle number of loading Bi₂O₃ nanoparticles. The photocatalytic activity of various samples may due to the different size of deposited Bi₂O₃, which can be observed by the field-emission scanning electron microscope (FE-SEM). The morphology may attribute to the growth controlling of ALD method. Then, a mechanism is proposed to explain why the compound with 10 cycle Bi₂O₃ shows the best behavior. Because that the Bi₂O₃ grown by ALD in several cycles is island, the photocatalytic was further improved by the structure of Bi₂O₃ nanoparticles/TiO₂ films. What's more, the sample had a good stability by keeping a high activity without obvious deactivation after four recycles of the degradation. The result shows that ALD technology has a broad potential application in the field of photocatalytic because its mass industrial production and the achievement of surface improvement in a short time.