Synthesis,Characterization And Application Of Silver/Copper/Cerium Metal-Organic Gel And Its Nanocomposite

The combined features of gel and nanoparticles can significantly improve the physicochemical properties of the resulting gel-nanocomposite material such as optical property,viscoelasticity,thermal conductivity,mechanical strength and so forth.The novel soft materials are finding more visibility with respect to their potential in diversified applications.There are different ways to prepare the gel-nanocomposites.One of the simple ways of the formation of soft nanohybrids started with the addition of preformed nanoparticles within the gel matrix.This composite can be also obtained by adding appropriate exogenous agents to reduce the gel molecular.Most popular way is to design molecular gelator with suitable functional groups to facilitate in situ synthesis and stabilization of the nanoparticles even at room temperature without the help of any exogenous reducing/stabilizing agents.This method eliminates the use of hazardous external reducing agents and extreme conditions.Furthermore,the self-assembly of small molecules can create an extensive variety of supramolecular architecture such as nanofibers,nanoribbons,nanosheets,nanospheres,helical and bundle structures,which can simultaneously offer desired ambience for the synthesis/stabilization of nanoparticles.Compared to traditional gels,the coordination interaction of metal ion and organic molecular impart metal-organic gel with special physicochemical properties and functionalities.Chemosensing,catalysis,adsorption and fluorescence applications are some of the many potential uses for these systems.The thesis mainly focuses on the synthesis of two sorts of metal-organic gel nanocomposites in situ.The two materials obtained have been characterized by 1H NMR,FT-IR,SEM,TEM,XRD,XPS,EDX,UV-vis,etc.They also could be used as adsorbent for dye molecular and heavy metal ion Hg(II)in aqueous system or as catalysts for the reduction of nitroarenes by NaBH4.Moreover,we also prepared two novel metal-organic gels and discussed the effects of the gels formation,studied the applications in fluorescence,chemical sensing and sensitization,respectively.The whole work can be summarized as five aspects:1.CuNPs@Cu(II)-AMTD metal-organic gel nanocomposite has been prepared with 2-amino-5-thiol-1,3,4-thiadiazole and Cu(Ac)2 in aqueous mixed solvent in situ.The material has been characterized by SEM,TEM,IR,SPR and EDX,etc.The effects of the gelatinization such as Cu(II)/AMTD stoichiometric ratio,counter anions,the sorts of solvents have been discussed in detail.The experiment data show that this composite could be used as excellent catalyst for the reduction of aromatic nitro compounds.2.We have explored the adsorption performance of Cu(II)-AMTD xerogel for ten organic dye molecules.The effects of adsorption time,absorbent dosage,initial dye concentrations,temperature and ionic strength have been investigated for three dyes: methyl orange,thymol blue and acid fuchsin.Adsorption kinetics,isothermal adsorption model and regeneration have also been discussed.This material is an excellent absorbent for sulfonic dyes in wastewater.3.AgNPs@Ag(I)-AMTD metal-organic gel nanocomposite has been synthesised in situ by AgNO3 and 2-amino-5-thiol-1,3,4-thiadiazole in aqueous mixed solvent.The composite has been characterized by 1H NMR,SEM,TEM,IR,SPR and EDX,etc.We have also discussed the effects of the the number and particle size of AgNPs such as Ag(I)/AMTD stoichiometric ratio and temperature.This composite could effectively absorbed heavy metal Hg(II)ion from wasetwater.The arguerite were formed in the gel and its composition is proportionated to the quantity of Hg(II)ion.So,the material has potential application in wastewater treatment.4.Cu(II)-BIF metal-organic gel was obtained with 2,7-bis(1-imidazole)fluorene and Cu(Ac)2 in DMF.The gel has been characterized by SEM,IR,EDX,etc.The effects of the gelatinization such as Cu(II)/AMTD stoichiometric ratio,counter anions,the sorts of solvents have been discussed in detail.The fluorescence “off-on” accompanied with the gel formation and collesped when it encounter ammonia.Therefore,the gel obtained can be used for flurrescence and chemical sensor for ammonia and the other gaseous amines.5.Ce-Asp metal-organic gel was synthesised by aspartic acid and Ce(SO4)2 in alkaline aqueous solution.IR,SEM and EDX were used to characterized the gel.The experiment results show that the gel matrix is an excellent sensitizer for Tb(III).Therefore,the gel added tiny amounts of Tb(III)could be used a potential LED soft material.