Controlled Synthesis And Photocatalytic Activity Of Bismuth Oxide And Its Composite

Semiconductor photocatalysts present very important meaning in the field of controlling environmental pollution and renewable energy exploration. Highly efficient photocatalytic activities of visible-light responded catalyst is the key to achieve effective usage of solar energy. Bismuth oxide is an attractive material because of its narrow band-gap and good photocatalysis to the refractory organic compounds under visible light irradiation. In the view of semiconductor catalyst is insufficient to use under the visible light, composite materials research has become one of hotspots in the field of international glazing catalyst materials research.1. Ag2O nanoparticle modified α-Bi2O3composite photocatalysts were synthesized and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV-vis diffuse reflectance spectroscopy. XRD patterns confirmed that the composites consist of cubic phase Ag2O and monoclinic α-Bi2O3phase. The Ag2O loading was greatly increased due to the rough surface of the acid etched Bi2O3microrods. Photocatalytic activity of the Ag2O-Bi2O3composites was evaluated using the degradation of methyl orange (MO). The correlation between the Ag2O content and photocatalytic activity was estimated. The composite with Ag to Bi ratio of3:1as raw material showed the highest visible light activity and the enhancement mechanism was attributed to the separation of photoinduced electron and holes by the carrier transfer.2. Three-dimensional (BiO)2CO3materials was synthesized by using hydrothermal method through controlled the ammonia content and characterized by XRD, SEM and TEM, etc. BET result shows that the material has high specific surface area, which is beneficial for the improvement of the photodegradation efficiency. The degradation of RhB solution was used to evaluate the photocatalytic performance of the material, shows the spherical mesoporous photocatalysts with relative narrow band gap and larger BET areas has better photodegradation efficiency.3. Bi2O3was synthesized through the hydrothermal process and the different morphologies effected on the photocatalytic properties were studied. By controlling the ammonia content, the precursor (BiO)2CO3was obtained. After the annealing treatment, spherical, flower-like and granular Bi2O3composed of connected particles was gained. Bi2O3with different morphologies were characterized by XRD, SEM and other characterizations. Finally, the influences of different morphology on the photocatalytic activity were investigated.