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.