| In recent years,many researchers found that the multifunctional nano-composite catalyst has potential application values in the physical adsorption,pharmaceutical intermediates synthesis,wastewater treatment,organic catalysis,aerospace fuel,and so on,multifunctional nano-composite catalyst has aroused close attention of researchers.In this paper,graphene oxide,prepared by modified Hummers method,was used as carrier,polyethyleneimine（PEI）was used as link agent and stabilizer,the modified Fe3O4 and titanium sulfate were used as the precursor,palladium acetate was uesd as the catalytic center.Finally,we have successfully prepared two kinds of novel nano-composite catalysts,Pd NPs/Fe3O4-PEI-RGO was called the magnetic nano-composite catalyst,Pd NPs/Ti O2/PEI-RGO was called the palladium doped Ti O2 nano-composite catalyst.For the two kinds of new nano-composite catalysts,firstly,the structure and morphology of the nano-composite catalysts were synthesized;energy dispersive X-ray spectroscopy（EDX）,ultraviolet visible spectrophotometer（Uv-vis）and Fourier Transform Infrared Spectroscopy（FT-IR）were used to establish element composition,chemical structure and containing functional groups of the material;In addition,X-ray photoelectron spectroscopy（XPS）and the X-ray powder diffraction（XRD）were used to detect the valence state of composite catalyst and crystal structure of particles;Finally,scanning electron microscopy（SEM）and transmission electron microscopy（TEM）were used to detect the all surface morphology of nano-composite catalyst and morphology of particles.Secondly,the catalytic activity was evaluated by degradation of a series of industrial dyes and organic pollutants.The optimum reaction conditions were selected by changing the p H value,the type and content of catalyst,and then,the catalytic activity of the catalyst was tested.The results show that the first kind of magnetic nano-composite catalyst,under the condition of Na BH4 solution as a reducing agent,showed excellent catalytic activity,the degradation rate and recovery efficiency of the degradation of industrial wastewater and organic pollutants.In addition,after thirteen cycles of repeated experiments,the magnetic nano-composite catalysts showed high stability and catalytic activity.Second kinds of palladium doped Ti O2 nano-composite catalyst,using the advantages of hydrothermal method,the reaction temperature is 180 0C,the reaction time is 12 h,the mass ratio of the palladium acetate,polyethylene and titanium sulfate is 1: 10: 50,the preparaed nano-composite catalyst was uniform size,good dispersion and diamond morphology.The reaction conditions are mild and the cost is low.The obtained nanocrystals are high purity,small size and large specific surface area,so that the photocatalytic degradation effect is remarkable.The results show that the metal ions doped into Ti O2 can improve the efficiency of photodegradation and the utilization of sunlight.In a word,the two kinds of new multifunctional nano-composite catalysts have uniform particle size,large specific surface area and remark able catalytic activity.Therefore,it is extremely suitable for the degradation of the industrial wastewater treatment. |
