Synthesis And Application Of CuO（NiO）@Al₂O₃Core-Shell Nanoparticles

Core-shell nanocomposite oxide has special optical, electrical and magnetical properties due to their different structures, sizes and composition arrangements. It also has good chemical stability and catalytic activity. Therefore it has broad prospects in the field of environment protection, catalysis, energy, etc.There are many ways to prepare core-shell structure materials. Reverse microemulsion method gets more attention because it has more advantages compared to other methods, such as the mild reaction condition, facile operation, controlled particle size, monodispersity, etc.In this thesis, CuO(NiO)@Al2O3nanospheres were prepared in the reverse microemulsion system formed by non-ionic surfactant (Brij(?)58), cyclohexane and glycol.(1) CuO@Al2O3was prepared using copper nitrate as copper source, triethanolamine as ligand and aluminum tri-sec-butoxide as the aluminum source. The particles have a narrow size distribution, with80%in30-34nm. The mean diameter was32nm. We explored the catalytic properties of the materials by the hydroxylation of phenol. An optimum reaction condition was obtained, that is t=2h, n(phenol):n(hydrogen peroxide)=1:1. Under the optimum condition, the conversion of phenol was38.2%, n(catechol):n(hydroquinone)=2.6:1.(2) NiO@Al2O3was prepared using nickel nitrate as nickel source, diethylamine as ligand and aluminum tri-sec-butoxdie as the aluminum source. We explored the catalytic properties of the material by the reaction of catalytic transfer hydrogenation (CTH) of nitroarene using isopropanol as hydrogen source. The conversion rate of aromatic nitro compounds was more than60%, and the reaction rate was faster than that reported in the literature. Dechlorination and catalyst poisoning were not observed during the reduction of aromatic nitro compounds with chlorine or low-valence sulfur.In addition, the materials were characterized by XRD, FT-IR, TG-DTG and TEM technologies. The effects of stirring speed, trace water, viscosity and reduction situation on the morphology of the material were also investigated.