Ag2O/TiO2 hollow microsphere heterostructures with exposed high-energy {001} crystal facets and high photocatalytic activities

In this paper, one-step hydrothermal method was used to prepare the graded titanium dioxide hollow microspheres, and the {001} crystal plane was exposed. The silver oxide nanoparticles were deposited on the exposed crystal face of titanium dioxide by wet chemical coprecipitation to form Ag2O/TiO2 composite material. The samples were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, nitrogen adsorption–desorption (BET), and so on. The degradation abilities of Ag2O/TiO2 composite materials with different molar ratios to rhodamine B were studied under UV–Vis irradiation. And then the mechanism of photocatalytic degradation was analyzed. The experimental results showed that when the molar ratio of titanium dioxide to silver nitrate was 4:1, the degradation effect was best, and the degradation rate reached 95.4% in 80 min. This outstanding photochemical catalysis performance was mainly due to good cooperation, including exposure of specific crystal planes of TiO2 hollow microspheres and highly scattered Ag2O nanoparticles, and the p–n heterostructure between Ag2O and TiO2 will induce efficient charge separation efficiency.