| Along with social,economical fast urbanized level enhancement,the environmental pollution problem has become a core problem that the world has to be faced.Large amounts of organic pollutants emission became one of the important sources that cause the deterioration of water environment.And the waste water inclusive of 4-NP is one of the most important contamination in water pollution.In recent years,with the development on semiconductor photocatalysis technology,the widely foreground on application of the catalytic degradation of organic pollutants were discovered.Semiconductor photocatalytic technology is applied in wastewater treatment because of its high catalytic oxidation ability,high efficiency advantages of recycling.But most of semiconductor photocatalytic materials contain metal components.It exhibits a narrow of light response range,a wide band gap,high consumption and easy to cause secondary pollution to environment and so on,which limits its practical application.With the research and development of graphite carbon nitride,the polymer type semiconductor photocatalytic materials research is proposed because the carbon nitride materials are a kind of excluding metal components,low cost,suitable band structure.The research and development of new photocatalyst materials and technology,which is aimed to enhance the absorption in the visible spectra range,has become a hot area in photocatalyst.According to the above-mentioned problem,a kind of polymer semiconductor photocatalytic materials is synthesized which has photoluminescence properties in this paper.And the application of the catalytic reduction of 4-NP is studied.The main contents are as following:1.M-phenylendiamine(mPD)and Rhodamine B(RhB)were used as monomers,ammonium persulfate as the initiator.Photoluminescent poly(m-phenylendiamine)-Rhodamine B copolymer dot(PmRDs)was synthesized by one step hydrothermal method.From experiments we found that it has good properties of photoluminescence,and it also has good absorption ability within a certain wavelength.Therefore it showed efficient catalytic performance in the catalytic reduction of p-nitrophenol(4-NP).Under the irradiation of xenon lamp,1×10-3 M 4-NP could be catalyzed by 6 mg/m L catalyst within 5 min,by calculating the rate constants up to 0.766 min-1(25℃).The pH,temperature,range of wavelength and catalyst dosage was also studied on the properties of 4-NP catalytic effect.In addition,compared with other catalysts containing metal components,we found that the catalytic activity of PmRDs was more outstanding under visible light.2.M-phenylendiamine(mPD)and Methyl orange(MO)were used as monomers ammonium persulfate as the initiator.Poly(m-phenylendiamine)-Methyl orange copolymer(Pm-MO)was synthesized by one step hydrothermal method.According to the experiments,1×10-3 M 4-NP could be catalyzed by 6 mg/m L catalyst within 6 min under the 24 W energy-saving lamps.We calculated the catalytic rate constant was 0.30 min-1 according to the first order kinetics equation.It shows excellent catalytic performance may be due to a more match band structure,narrower band gap,and has a good photocatalytic activity.3.Since Rhodamine B and methyl orange belongs to dye molecules,they may cause secondary pollution to the environment.So we found that chlorophyll has strong absorption of red light and blue purple light.However,the spinach has chlorophyll richly.In this experiment,we use m-phenylene diamine and spinach juice as raw material,synthesized a polymeric material with photocatalytic performance.From structural characterization and performance tests,we found that 4-NP could be catalyzed within 60 min under the ultraviolet lamp. |
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