Synthesis And Properties Of Oxide Nanocomposites

Oxide nanocomposites have demonstrated great vitality in the field of nanomaterials due to their superior comprehensiveness and designability in performance applications.This thesis mainly discusses the synthesis methods of oxide nanocomposites,and on this basis,a series of characterization methods(such as TEM,SEM,FTIR,TG,XRD,etc.)are used to explore the effects of different reaction conditions and additives on the synthesis of oxide nanocomposites and the changes in their properties.The main contents are as follows:1.Preparation of bimetallic oxide hollow nanoboxes and study on their catalytic performance.In this system,a series of bimetallic complexes(Fe/Cu/Ni/Ag-ZIF-67)were synthesized by the coordination of Fe(Ⅲ),Cu(Ⅱ),Ni(Ⅱ)and Ag(Ⅰ)with the surface ligands of ZIF-67.After calcining in an oxygen atmosphere,these prepared bimetallic complexes were converted into bimetallic hollow nanoboxes(Fe/Cu/Ni/Ag-BHN)doped with Fe(Ⅲ)/Cu(Ⅱ)/Ni(Ⅱ)/Ag(Ⅰ)by Kirkendall effect and achieved good catalytic effects of hydrogen production catalysis of CO and ammonia borane.In summary,we have found a simple and universal method for the formation of bimetallic oxide nanomaterials.The method is to form bimetallic oxide hollow nanoboxes after the second metal ion is combined with the ZIF-67 surface ligand and then calcined at high temperature.2.Synthesis of Fe3O4 and FeMnOx nanopaticlesIn this work,we have developed a method to synthesize high yield MOx(M=Fe,Mn-Fe)nanoparticles by thermal decomposition of commercial iron oxide materials with the solution of thermal surfactant Fe3O4 NPs can be synthesized from different types of commercial iron oxide precursors,such as commercial α-Fe2O3,γ-Fe2O3,Fe3O4.The size of MOx nanopaticles can be controlled precisely by adjusting the molar ratio between the surfactant and the iron precursors.During the synthesis process,the surface ligand types of Fe3O4 NPs can be adjusted by adding surfactants with different carbon bond types and carbon chain lengths,and the bimetallic composite oxide nanoparticles are synthesized by introducing commercial MnO2 containing the second metal element.This method is simple and easy to operate,can synthesize a large number of highly uniform and stable monodisperse nanopaticles at one time.3.Synthesis of MnO and ReMnOx nanopaticlesHomogeneous monodisperse MnO NPs was synthesized by using different commercial manganese precursors(MnO,MnO2,Mn3O4)of micron scale.Moreover,by adjusting the molar ratio between the surfactant and the metal oxide precursor,the size of MnO NPs can be precisely controlled,and the morphology of MnO NPs can be affected by adjusting the quality of NaOA.The MnO NPs synthesized by this method has good stability and high dispersibility,and can be volatilized at room temperature to obtain regular array assembly.Finally,Re doped ReMnOx nanopaticles with fluorescence properties were synthesized by this method,which endowed these oxide nanopaticles with fluorescence properties.