| Semiconductor photocatalysis technology is one of the most promising technologies and is widely used in many fields,such as energy development and environmental pollution.Compared with other semiconductors,titanium dioxide（Ti O2）has the advantages of high catalytic activity,strong photooxidation,stable chemical properties,and abundant sources of raw materials.It has gradually become a research hotspot in environmental applications ranging from deodorization to air and water purification.Ti O2 has a wide energy band,only responds to ultraviolet light,and has low quantum efficiency.To use solar energy more effectively,the absorption spectrum of Ti O2 must be extended to the visible light region,and 45%of the solar energy in the visible light region must be utilized.Based on the deficiencies of Ti O2,researchers have prepared Ti O2 nanomaterials with different morphologies.Due to their different morphologies,they exhibit different material properties.Next,the surface is modified with noble metal oxides,and at the same time,the excellent properties of graphene and graphene carbon nitride（g-C3N4）are used for further coating.The prepared nanocomposite material significantly improves photocatalytic activity.This topic is mainly divided into three parts to carry out research and analysis:（1）Preparation of Ag2O/Ti O2 composite material by hydrothermal method and wet chemical co-precipitation method.The prepared composite materials were characterized by XRD,SEM,TEM,XPS,and other test methods.Under UV-Vis light,the degradation ability of Ag2O/Ti O2 composite material to Rhodamine B（Rh B）pollutants was studied.The experimental results show that when the molar ratio of Ti O2 and Ag NO3 is 4:1,the degradation rate of the material is 95.4%within 80 min.This excellent photocatalytic performance is mainly due to good synergy.It is embodied in the specific crystal plane exposure of Ti O2,highly dispersed Ag2O nanoparticles,and the p-n heterojunction structure of Ag2O/Ti O2.（2）Preparation of nanoflake flower-like r GO-Ag2O/Ti O2（r AT）ternary composite material,using two-step hydrothermal and one-step wet chemical co-precipitation.Under UV-Vis light,the degradation rate of r AT ternary composite is 92.3%within 70min.The data shows that the material has high catalytic activity.The main reason is that the three elements of r GO,Ag2O,and Ti O2 have particularities in morphology,performance,and structure.Ti O2 has the morphological characteristics of layered flakes,Ag2O has the performance characteristics of narrow bandgap and excellent dispersion,and r GO has the characteristics of two-dimensional network structure.It is further discovered that in terms of design ideas and preparation methods,the r AT ternary composite photocatalyst will provide a new vision and brilliant prospects for photocatalytic materials.（3）To prepare Ti O2 and g-C3N4 samples by simple hydrothermal method and calcination method respectively.The g-C3N4@Ti O2 hollow microspheres were further prepared by the water bath evaporation method.This work mainly regulates the amount of g-C3N4 parameter and strives to prepare composite samples with better photocatalytic activity.Therefore,finding the most suitable g-C3N4 content has become the main task of this work.By degrading the catalytic effect of the Rh B solution,to compare the degradation of a series of samples.Finally,when the weight ratio of g-C3N4 to Ti O2 is15%,the sample prepared in this way（15%g-C3N4@Ti O2）has the best photocatalytic effect.Within 90 min,the degradation rate of 15%g-C3N4@Ti O2 composite material was 90.8%. |
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