Study On Synthesis And Catalytic Properties Of Novel Metal Nanomaterials

In recent years, the development of nanoscience and nanotechnology has been widely penetrated into many other disciplines; one of the most typical examples is the design, synthesis and development of new nanomaterials, and application in catalysis. Nanocatalysts show outstanding features unmatched by many conventional catalysts. Therefore, study on synthesis of novel nanomaterials and their application in catalysis is becoming the hotspot of the catalytic chemistry.Fe2O3nanotubes, CuO@Ag nanowires and Fe3O4@Cu nanoparticles were synthesized by template method and liquid-phase synthesis respectively. These nanostructures were characterized by SEM, TEM, XRD, HRTEM, EDS and so on. Then the catalytic properties of the nanostructures were investigated. The work includes three aspects:1. The Fe2O3nanotubes were prepared by directly coating silver nanowires with conformal sheaths of Fe2O3by thermal decomposition of Fe(CO)5, and then selective removal of the silver cores. The thickness of Fe2O3coating could be controlled by changing the concentration of the precursor solution. The as-prepared Fe2O3nanotubes serve as nanoscale reactors for oxidation of alcohols with good catalytic property.2. We designed a novel structure nanomaterial using Ag nanowires to carry CuO nanoparticles (CuO@Ag nanowires). The CuO@Ag nanowires show outstanding catalytic activity and selectivity when used as the catalyst in the epoxidation of trans-stilbene with the green oxidant of air. At the same time, the CuO@Ag nanowires also show excellent catalytic activity in the oxidation of alcohols at low temperature using tert-butyl hydroperoxide (TBHP) as the oxidant.3. We demonstrate a wet-chemical synthesis approach to synthesize a Fe oxide shell around Cu core nanoparticles (referred to as Fe3O4@Cu). The heterodimer nanocrystals exhibit good activities for selective oxidation of olefins and alcohols. Furthermore, the nanoparticle catalyst could be easily separated from the product mixture by using a magnet and could be recycled several times without losing catalytic activity.