Synthesis, Characterization And Catalysis Application Of Au Pd-TiO₂

Nobel metal-oxide nano-hybrids have tremendous potential in material science research and catalytic application and have become research hotspots in the material field, because the nano-hybrids have the Physical chemical and optical properties of both nano-oxide and nano-noble metal. What’s more, there is synergistic effect between noble metal and oxide. Nano-hybrids including Au-TiO2,Pd-TiO2,AuPd-TiO2 have great application potential in alcohol oxidation, hydrogen peroxide synthesis, carbon monoxide oxidation, thus gradually attract people’s attention. In my paper, we focus on the development of a new green chemistry-compatible method to prepare hybrids: Au-TiO2, Pd-TiO2, AuPd-TiO2, and then do a detailed characterization of the hybrids, analyze the interaction among the components, study the catalytic application of it. Detailed content as following:1. Using RTIL-aided sputtering method with Au and Pd target as sources, we prepared AuPd-TiO2 nano-hybrids with different AuPd ratio in a controlled manner, and we studied the morphology, chemical composition and electronic structure of fabricated hybrids using TEM, XPS, XRD, Uv-vis and XANES. Results indicated gold and palladium particles distribute uniformly on surface of TiO2 supporter, the size of bimetal particles are uniform, Au and Pd elements distribute uniformly in bimetal NPs; characterization of electronic structure showed that there is electron transfer among TiO2, Au and Pd.2. Using the hybrids with different AuPd ratio as catalysts to catalyze 1-phenylethanol oxidation, we studied the effect of composition ratio on the catalytic ability of the hybrids; analyzed the reasons of the effect.3. We prepared TiO2 supporter with oxygen vacancy, referred to TiO2(OV) by chemical vapor deposition tube furnace under hydrogen atmosphere and did characterizations of the TiO2(OV), and then used sputtering to load Au nanoparticle on it, and characterizations of the hybrids were done.4. Using the hybrids mentioned as catalysts to catalyze reduction reaction of 4-nitrophenol, results showed that oxygen vacancy had promotion effects on the catalytic ability of the hybrids.Based on the related research results in my paper, compared with the traditional method(metal ion reduction method), the method in my paper has many advantages, such as simple preparation process, be friendly to environment and good controllability of the size of metal nano-particles. The results of catalytic tests showed that for the solvent-free oxidation of 1-benzyl alcohol under mild condition(mild pressure and mild temperature), the nano-hybrids showed high catalytic activity. The method is efficient, free of by-products and no-addition of stabilizer. All characterizations including morphology results, electronic structure results and optical absorption results showed the successful and controllable preparation of the nano-hybrids. We also found that the catalytic activity of the prepared nano-hybrids is associated with the AuPd ratio in the hybrids. What is more, this can be controlled by the IL-assisted sputtering method.