| With the development of basic research and practical process of nanometer technology, nanometer material as a potential efficient new functional environmental protection material in the environmental protection field is valued.At present, the TiO2 regared as typical semiconductor optical catalyst, although it has high photocatalytic activity and stability, but its quantum efficiency of photocatalytic system is still not enough high, and it is hard to use the visible light which occupied the main part in natural light. In the contrary, FeOOH although can absorb visible light, but the photocataly ticactivity is not high enough.As the advantages and disadvantages of two kinds of light semiconductor optical catalyst, we can composite them into a new compound semiconductor materials to improve to the natural bare catalytic activity. Meanwhile,with the differences of the existing oxidizing catalyst undulations emphatically study, this paper mainly researches this composite light catalyst reductive effect of heavy metal ion in wastewater,in visible light,explores it become a new technology of heavy metal wastewater treatment, which has theoretical and practical value.Based on taking quartz glass as basement, taking functional groups of mercaptoacetic (SH) for the self-assembled interfacial monolayer as templates, and using molecular self-assembly methods, makes nanometer FeOOH/TiO2 in compound film in low-temperature liquid reaction system. And with silver ions as objects, discusses for the FeOOH/TiO2 photocatalytic reduction ability in the influence of different experimental conditions, the main research progresses of the paper are as follows:(1) Using the molecular self-assembly methods, in specific surface area of 4.4×10-3m2 quartz glass respectively made FeOOH,TiO2,TiO2/FeOOH, FeOOH/TiO2 four film.Through the transmission electron microscopy to confirm the characterization of composite film compound film is composing and growth of sharp over-mining and goethite.(2) Takes Sulfuric acid silver solution for targets, inspects the photocatalytic reduction ability of composite membrane and single-layer film. Conrtoning the same experimental conditions:initial concentration for silver ions be 1×10-3mol/L, the ultraviolet light, the ability of reaction on silver reductive is:TiO2> TiO2/FeOOH> FeOOH;Visible light, in the same experimental conditions, three films were reaction of silver the reduction of ability strong or weak order is FeOOH/TiO2> FeOOH> TiO2;In addition, the conditionscatalytic activity of TiO2/FeOOHis higher in the visible than in the uv light.(3)As sulfuric acid silver solution for targets, inspecting the condition of photocatalytic reduction ability of composite flim under membrane layer order in different coating. Under the same experimental conditions:iInitial concentration in silver ions for 1×10-3mol/L, visible light, the photocatalytic reduction ability of FeOOH/TiO2 is stronger than TiO2/FeOOH about 25.4%.(4)As sulfuric acid silver solution for targets, inspecting the condition of photocatalytic reduction ability of FeOOH/TiO2 in different light conditions with time. Under the same experimental conditions:Initial concentration in silver ions for 1×10-3mol/L, visible light, the reaction time such as 40min,20min,60min,the photocatalytic reduction ability of FeOOH/TiO2 weakened gradually over time(5) As sulfuric acid silver solution for targets, inspecting the condition of photocatalytic reduction ability of FeOOH/TiO2 in different initial concentration of silver ions.Under the same experimental conditions:the same reaction time,visible light, in the different initial concentration of silver ions:1×10-3mol/L,1×10-4mol/L,the rate of reduction of silver ions respectively is 99.0%and 40.9%. For less than 1x10-4mol/L silver ions composite membrane can almost completely reducted..(6) Combined with the affective factors of reaction system, such as different illumination conditions,different coating stratigraphy,different reaction time and different silver ion of initial concentration. ect, discussing the Light catalyzing of mechanism of FeOOH/TiO2 composite film, and the Photocatalytic reduction silver ions of the FeOOH/TiO2 composite films maybe need two process.They are silver ions adsorption and reduction.
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