Construction Of Organic-Inorganic Hybrid Supramolecular System Based On Host-Guest Recognition

Organic-inorganic hybrid materials have been widely used in sensors, biological materials, nanoelectronics and catalytic materials, due to their excellent strength, catalytic, optical and electromagnetic properties. Although great progress has been made in this field, it is still a big challenge to prepare hybrid materials with stimuli-response in a simple method, which may improve their efficiency and exploit the applications.In this thesis, based on the current research status of organic-inorganic hybrid materials, and our research results of host-guest chemistry, we prepared two kinds of organic-inorganic materials with pH-response as well as electrochemical- and competitive guest-responses. This thesis was composed of four chapters. In the first chapter, the properties and applications of nanocomposite materials as well as the host-guest chemistry were introduced.In the second chapter, amphiphilic pillararene AP5 was synthesized and the complexation behavior was investigated for the first time. The amphiphilic pillararene AP5 was synthesized via the ammonolysis reaction of an unsymmetrical pillararene derivative NP5, which was synthesized through the Fridel-Crafts reaction of monomer (methyl 2-(4-(hexyloxy)phenoxy)acetate). The structures were characterized by 1H NMR,13C NMR and X-ray diffraction. TEM and SEM results demonstrated that AP5 could self assemble into vesicles, which could transfer into micelles in pH 3 or disassembled into irregular aggregates. For the first time, the complexation of AP5 with alkyl chains was investigated, which exhibited pH-response. This work provides references for selecting the guest molecules of amphiphilic pillararenes.In the third chapter, AP5-SiO2 hybrid vesicles were prepared by combining the self assembly process of amphiphilic pillararene and the catalytic hydrolysis of tetraethoxysilane (TEOS). The introduction of silica into the vesicles can not only greatly improve the strength of the composite, but also improve the loading capability and tune the speed of release. Most importantly, for the first time, a rhodamine B derivative with hexyl group was selected as a new guest molecule to investigate the host-guest complexation between AP5 and RhB-C6, which can also tune the process of release. One can envision it may be helpful for the fabrication of functional materials and definitely bring about many promising applications, such as sensors, nanodevice, drug delivery and controlled release.In the fourth chapter, cyclodextrin modified gold nanoparticles were prepared and a novel guest (ferrocene modified rhodamine derivative, Fc-RhB) was designed and synthesized. Based on the complexation of cyclodextrin with ferrocene and the π-π interaction of rhodamine groups, the aggregation of gold nanoparticles was realized, which could be dissociated futher by the electrochemical-response of ferrocene or addition of competive guest molecules. Multiresponsive hybrid gold nanoparticles were constructed by employing dual non-covalent bonds, which provides a new method to prepare hybrid materials with stimuli-responses.