Preparation And Properties Of Multi-functional Nano-composites Of Rare Earth

Luminescent complexes of rare earth possess good optical properties.However,the materials with single luminescent function could not meet the needs,so luminescent complexes of rare earth sometimes were combined with functional inorganic compound or organic polymers.Therefore multi-functional hybrid materials of rare earth with excellent properties could be obtained.As we know,many noble metal nanoparticles show unique optical,electrochemistry and catalytic properties,which are concerned by scientists in many fields.In this paper,the materials of rare earth were combined with noble metal nanoparticles,and the multi-functional materials with fine luminescence and catalytic properties were prepared.poly?N-isopropylacrylamide??PNIPAM?showed obvious temperature sensitivity,which was widely used in drug release,catalysis,chemical separation,medical material and enzyme.Multi-functional materials with temperature sensitivity properties could be obtained when luminescent rare earth complexes were combined with gold,silver or polymer materials.In this paper,temperature sensitive polymers were combined with luminescent rare earth and gold or silver nanoparticles,and multi-functional hybrid materials with controllable luminescence and catalysis were obtained.There are three parts in this paper:1?The slica spheres with different sizes were synthesized by Stober method and their surface were modified.The lanthanide-polyoxometalates EuW₁₀ were grafted on the surface of silica spheres,and SiO₂/EuW₁₀ composite sphere were obtained.Then gold nanoparticles were in situ grafted on the surface of SiO₂/EuW₁₀ composite particles.The samples were characterized by UV-vis,XRD,SEM,TEM,luminescence,CV and so on.The results showed that the grafted gold nanoparticles on different spheres had various sizes,and luminescence properties and catalytic efficiency of composite were different.2?The multi-functional SiO₂/EuW₁₀/Au/PNIPAM composite materials were synthesized in this chapter.The samples were characterized by IR,XRD,SEM,TEM,luminescence.The composite materials showed the obvious core-shell structure.The composite showed the higher catalytic efficiency at room temperature than that at higher temperature.The composites showed red luminescence under UV light at room temperature,which could be obversed with naked eye.However,red luminescence disappeared at higher temperature.The composite nanoparticles showed different catalytic and luminescent properties at diferent temperatures because of temperature sensitivity of PNIPAM.3?SiO₂/EuW₁₀/Ag/PNIPAM multi-functional composite nanomaterials were synthesized in this chapter.The composite nanomaterials were characterized by UV-vis,SEM,TEM,luminescence.The composite nanomaterials showed good fluorescenc and catalytic performance.Rhodamine B could be reducted quickly at room temperature by the composite nanomaterials.However,the reaction rate at high temperature was lower.The composites showed red luminescence under UV light at room temperature,which could be obversed with naked eye.However,red luminescence disappeared at higher temperature.The above results indicated that the composite nanoparticles showed controllable luminescence and catalytic properties because of temperature sensitivity of PNIPAM.