Study On Detection Of The Cr(?)?Hg(?)and VOCs By Functional Nano-porous Materials

With the rapid development of industry and agriculture,people are not only enjoying the convenience brought by it,but also affected by many negative problems.Large emissions of waste water,waste gas,which results in heavy metals ions and organic pollutants in the environment gradually increased,and cause a serious threat to human health.So the detection for heavy metal ions in environmental water resources as well as volatile organic pollutants(VOCs)in the atmosphere are very necessary.In this study,we used functionalized nano-porous material and successfully achieved the detection for Cr(?),Hg(?)in aqueous solution as well as VOCs in the atmosphere,the main research contents and results are as follows:(1)Based on PET nano-materials,we prepared a series of single asymmetric nanopores with different diameter by wet etching method and independently loading on the surface,then through a series of characterizations the PET nanofilm,such as ?-? curves,XRD and Raman spectra,we can draw the conclusion that the completed autonomy of conical nanopores have been successfully implemented on Cr(?)and Hg(?)detection.(2)The etched PET nanofilm surface with a large number of carboxyl and hydroxyl,the groups themselves are good metal ions chelating agent.Under the experimental conditions at pH=8.0,through a specific metal ion chelators(EDTA)interaction,achieved the study on selective sensitivity testing toward Cr(?).The method with a detection limit is 16 nM,as opposed to other methods is a very broad application prospects,with good repeatable regeneration and selectivity.This method is simple and avoiding the tedious modification processes,it has a very broad application in the near future.(3)Using autonomous technology,assembled in PET nanofilm surface polyethylenimine(PEI)and Zr4+.By SEM,?-? curves and XRD characterization of the nanopore surface.strong Zr4+ have strong binding capacity with PO43-of nucleic acid.We selected T-rich nucleic acid chain,through the specificity of T-Hg2+-T structure,combined with single-walled carbon nanotubes has achieved the specific detection for Hg2+.The detection limit of this method for Hg2+ detection is 8.3 nM and with good selectivity,it can be successfully applied to the actual detection of Hg2+ in water samples.This method has broad application prospects.(4)In this article,Pd@Fe3O4 nanoparticles were successfully synthesized and characterized by XRD,EDS,TEM,SEM.It was used as gas sensing materials to construct gas sensors for VOCs detection.The optimal operating temperature of the sensor is 300 ?,and it is fast,sensitive,stable to VOCs gas,the response time of the ethanol is only 18 seconds,the recovery time is about 30s.The gas sensor preparation were investigated on 12 kinds of volatile gases,showed the good detection effect.(5)This article around with functionalized nano-porous materials study on the detection of Cr(III),Hg(II)and VOCs in the environment,and to conduct research has achieved certain results in their detection.Since nano-porous materials with high porosity,large surface area,surface activity,optical absorption,photoluminescence properties,strong adsorption capacity and other unique physical and chemical properties,which have aroused people's wide concern.The sensor based on functionalized nano-porous materials for environmental pollutants detection has been proved to be a fast,economical and practical methods,which has broad prospects in the future.