Preparation Of Layered Copper Hydroxide Nitrate And Catalytic Wet Oxidation Degradation Of Methyl Orange

Layered hydroxide salts(LHSs)have brucite-like structures,in which a portion of the hydroxide groups are replaced by water molecules and/or anions,resulting in the formation of compounds M2+(OH)2-x(Am-)x/m·nH2O.The properties of the LHSs compounds can be modified through stripping/intercalation,anion exchange,and surface grafting reactions.Copper hydroxide nitrate(Cu2(OH)3NO3),as a typical layered hydroxide salt,has been extensively studied mainly because of its low cost and special structure.It has been widely used as a catalyst,and the precursors of copper oxides.This master thesis has studied the preparation of layered Cu2(OH)3NO3 nanoplates and their application in catalytic wet oxidation degradation of methyl orange.The specific contents are as follows(1)Preparation of Layered Cu2(OH)3NO3 Nanoplates Layered Cu2(OH)3NO3 nanoplates were prepared on ZnO substrate through slow hydrolysis of Cu(NO3)2.The Cu2(OH)3NO3 nanoplates have large smooth surfaces,straight edges,sharp tips,and unique layered structure.The XRD characterization indicates the layered Cu2(OH)3NO3 nanoplates are monoclinic single crystals with exposed large(001)surfaces.It was discovered that the morphology of ZnO substrate has significant effect on the growth of Cu2(OH)3NO3 nanoplates.The Cu2(OH)3NO3 nanoplates grown on ZnO networks have higher density and smaller mean size.They gather together to form flower-like assemblies.On the other hand,the Cu2(OH)3NO3 nanoplates grown on ZnO films have lower density and larger mean size.In addition,this master thesis has also used the layered Cu2(OH)3NO3 nanoplates as precursors to prepare CuO porous nanopaltes(2)Catalytic Wet Oxidation(CWO)Degradation of Methyl Orange Comparing to the layered Cu2(OH)3NO3 nanoplates prepared through hydrolysis of Cu(NO3)2 in basic solution,the layered Cu2(OH)3NO3 nanoplates grown on ZnO exhibit higher catalytic activity for the CWO degradation of methyl orange.Under dark condition,95%methyl orange was degradated within 20 min(3)Growth Mechanism of Layered Cu2(OH)3NO3 Nanoplates We have also investigated the growth of Cu2(OH)3NO3 nanoplates on different oxide subtrates,including ZnO,CuO,and NiO.It was discovered that the layered Cu2(OH)3NO3 nanoplates can only be grown on ZnO and CuO subtrates.While keeping the other experimental condition be the same,the growth of layered Cu2(OH)3NO3 nanoplates on ZnO is much faster than that on CuO.We believe the growth of layered Cu2(OH)3NO3 nanoplates on ZnO was assisted by the negatively charged O-surfaces of ZnO.Specifically,the O-surfaces interact with H2O and release the OH-ions from the water molecules.As a result,the hydrolysis of the Cu(NO3)2 precursors was greatly promoted to form the layered Cu2(OH)3NO3 nanoplates.