Synthesis Of The Smart Nanoreactor With Photo-responsive Molecular Switch And Its Controlled Catalysis Property

It has been an important task for researchers to prepare efficient and stable catalysis material with the development of modern catalytic technology. Metal nanoparticles have been widely used in the field of catalysis for their excellent performances, but it also have disadvantages like easy agglomerating and being inactive when exposed to external environment. The method of using nano materials as carrier of catalyst can not only avoid the defects of nanoparticles effectively, but can also make reactors more intelligent in controlling reaction process. The development of synthetic chemistry and smart materials have provided theory evidence and foundation for the preparation of new catalyst carrier. We have prepared photo-sensitive nanoreactors by using amino modified mesoporous silica as carriers of catalyst in this paper.We combined the photosensitive nano materials with the silver nanoparticles as intelligent nanoreactor. Our preliminary study showed that cyclodextrin cavity and trans azobenzene has strong interaction, whose binding constant of 2.0×103 M-1;The cis azobenzene and cyclodextrin almost have no interaction. They cannot effectively form a composite structure. Because the cis and trans structure of azo phenyl group can transform each other in different wavelength of light. Azo phenyl group and cyclodextrin will be reversible composite(430 nm) and solution composite(365 nm)process under the effect of outside light stimuli.The photo-sensitive nanoreactor was prepared by the inorganic porous materials with photo-sensitive and silver nanoparticles. Here, we chose the two carboxyl azobenzene(Azo) as photo-sensitive group of reactor, because azobenzene and cyclodextrins can exhibit reversible photo-induced composite- separate effect by azobenzene heterogeneous when exposed to certain wavelength of UV light. The reactor prepared in this experiment was comprised by modification of mesoporous silica and azobenzene and cyclodextrin supramolecular complex system. We chose mesoporous silica(MS) to contain silver nanoparticles. The channel of nanoreactorhas reversible photo-induced "on/off" effect: the reactor was exposed to λ=430nm Visible light, then the azobenzene can be compound with cyclodextrin. It also resulted in the difficult access of reactants to silver particles and slowed down the reaction rate.The photo-sensitive nanoreactor will be dismissed when exposed to λ=365nm UV light. It also resulted in the easy access of reactants to silver particles to increase the reaction rate.Photo-sensitive nanoreactors were used as carriers of catalyst in preparing novel catalyst reactor with "on/off" channel effect in this paper. We also did several analysis tests to study reactors’ property and performance like photo-sensitive nanoreactor,channel’s "on/off" effect of photo-sensitive nanoreactors and regulation mechanism for catalytic reaction. The method of preparing intelligent nanoreactor by using smart nano materials have provided new methods and ideas for designing and synthesizing novel catalyst carriers.