Preparation Of Clay Minerals/TiO₂/Cu₂O Photocatalyst And Study On Its Algae Killing Properties

Eutrophication of water bodies is becoming more and more serious,and algae grow in large numbers.The outbreak of cyanobacteria caused by eutrophication of water has become a major environmental problem that restricts the sustainable development of our society and national economy.Therefore,it is an urgent problem to find a material with high efficiency,environmental friendliness and resource conservation.Photocatalytic oxidation method is the water treatment technology in recent years.In water treatment technology,the photocatalytic oxidation process has the characteristics of high efficiency and no two pollution.It has been used in the photocatalytic degradation of organic matter and removal of algae.In this paper,the clay minerals/TiO₂/Cu₂O composites were prepared based on p-type semiconductor Cu₂O and n-type semiconductor TiO₂.The ability of Cu₂O to be excited by visible light,together with TiO₂,to form a composite semiconductor system.Combined with clay minerals?this paper selects rectorite and hydrotalcite?to capture Microcystis aeruginosa cells and to control Cu₂O,integrated photocatalytic removal of algae system can be realized.Take full advantage of Microcystis aeruginosa bloom outbreak time,according to the full,supersaturated,dissolved oxygen and other natural laws,to achieve the governance of Microcystis bloom water.The main research contents are as follows:1.Rectorite/TiO₂/Cu₂O and HDL/TiO₂/Cu₂O composite materials are prepared by co-precipitation method..The crystal structure,morphology,light absorption and specific surface area of Rectorite,Hydrotalcite,Cu₂O,TiO₂ and its composites were analyzed by XRD,SEM,TEM,Uv-vis DRS,BET and so on.2.The p-n heterojunction structure of Cu₂O and TiO₂ was studied.We studied the formation of heterojunction structures,the expansion properties of heterojunction structures on the response range of light,the promoting effect of heterojunction structures on carrier separation,the inhibitory effect of heterojunction on carrier recombination,and finally The effect of heterojunction on the photocatalytic performance.3.Taking Microcystis aeruginosa as the dominant target,the photocatalytic activity of the composite system constructed with clay mineral/TiO₂/Cu₂O was tested.And by changing the dosage,illumination and oxygen content,the influence of natural environment factors such as light,oxygen and other factors on the algae killing properties of clay mineral/TiO₂/Cu₂O system was studied.4.By measuring Rectorite/TiO₂/Cu₂O and hydrotalcite/TiO₂/Cu₂O photoca-talyst algaecide two kinds of three recycling experiments,and the simultaneous determination of copper ion concentration in solution algicide photocatalytic process,we studied the photocatalytic stability of the algae agent.At the same time,the algae removal mechanism of clay mineral/TiO₂/Cu₂O system was investigated by photocatalytic removal of algae in different systems.The results shows that the clay minerals in the clay mineral/TiO₂/Cu₂O composite materials were good for the adsorption of algal cells.And the p-n heterojunction structure of TiO₂/Cu₂O composite semiconductor enhanced the photocatalytic effect of semiconductor.So that the clay mineral/TiO₂/Cu₂O semiconductor photocatalyst has good algicidal effect.