Synthesis And Property Of Metal/Metal Organic Framework Hybrid Materials

Both noble metals and metal-organic frameworks (MOF) have wide applicationpotentials in many fields, such as sensors, catalysis and biomedicine. It is known thatthe physical and chemical properties of materials are closely related to their size,morphology and composition. For the metal/metal-orgainc framework hybridnanomaterils, how to avoid migration and self-aggregation of noble metal nanoparticlesand MOF themselves is of great significance. So, development of novel synthesisstrategies remains an important challenge. This dissertation focuses on design andsynthesis of metal-MOF core-shell and yolk-shell hybrid nanomaterials as well as theiroptical properties and further applications in sensor and biomedicine.1. A facile one-pot synthesis method has been developed for synthesis of core-shellAu@MOF-5nanoparticles by controllable regulation of crystal nucleation and growthprocesses. The size and shell thickness of the core-shell Au@MOF-5nanoparticles canbe tuned by adjusting the reaction conditions. It is noteworthy that the core-shellAu@MOF-5nanoparticles with a shell thickness of (3.2±0.5) nm show unique surfaceenhanced Raman scattering (SERS) activity toward CO2in mixture gases,demonstrating the potential application in sensors for the selective detection of CO2molecules. Moreover, highly uniform yolk-shell Au@MOF-5materials are easilysynthesized by changing the reaction ratio of the precursors, which can be used ascontrolled-release systems. Due to their easy preparation and dual nature of both thecores and the shells, the core-shell or yolk-shell noble metal@MOF hybridnanomaterials are expected to have extensive applications in the area of nanoreactorsand targeted drug delivery.2. A facile hydrothermal approach has been introduced to fabricate core-shellAu@ZIF-8hybrid nanomaterials. We have succeeded in preparing monodispersecore-shell Au@ZIF-8hybrid materials by easily changing the reaction conditions. Thecore-shell Au@ZIF-8nanoparticles show low toxicity and good biocompatibility. Thisis the first report about core-shell NP@MOF hybrid nanomaterials acting asmultifunctional drug delivery systems. Impressively, such core-shell Au@ZIF-8nanoparticles not only have a high drug payload but also exhibit the light-controlled drug release property. Moreover, two cancer therapeutic modes for cancer theragnosis,hyperthermia and thermotherapy, have been observed under light irradiation forintracellular drug release.3. A green method for synthesis of monodisperse ZnS supraparticles is developedby using MOF as the template. Such ZnS supraparticles exhibit a highly efficienetphotoinduced reductive dechlorination activity toward PCB153under ultraviolet light.Impressively, this simple synthesis method is suitable for large-scale preparation ofmetal sulfide nanomaterials owing to its mild reaction conditions.