Structural Construction For Advanced Catalytic Performances Of Nanocatalytic Materials MO₂（M=Ti And Ce） Supported By Merals

Design and synthesis of catalytic materials are crucial for developing catalytic science and the relevant technologies. Up to now, nanocatalysts are still chanllenged by low efficiency, unstability, and ambiguous catalytic mechanism, which to a great extent restrict the further development of catalytic science. In this work, we initiated a structural construction to prepare metal supported oxide nanocatalysts and explored the catalytic mechanisms for advanced performance. The main results can be summarized as follows:(1) TiO2hierarchical microspheres constructed by rutile nanowires were fabricated through a solution chemistry route. The growth kinetic equation of building block nanowire for microspheres was obtained by systematically adjusting the preparation variables like reaction temperature and duration. Detailed experimental characterizations and photocatalytic performance measurements indicated that the bulk appearance for microspheres showed large surface area, lattice expansion, and excellent photocatalytic activity, which may result from the specific exposed crystal facets and highly electronic conductivity along the direction [001] for microspheres. (2) Pt nanoparticles were deposited onto the specific crystal facet of micrpspheres through a photoreduction strategy. Further, the optimized photocatalytic activity was achieved by tuning the Pt content supported on TiO2. Experimental results indicated that TiO2microspheres with0.85wt%Pt depositing showed an excellent photocatalytic performance, comparable with that of P25under UV light irradiation, and that superior to P25under visible light irradiation. Moreover, based on these observations, reasonable catalytic mechanisms were proposed.(3) Ag/CeO2core-shell nanospheres were constructed through one step redox route. The enhanced interface interaction between core Ag and shell CeO2by heating treatment resulted in a complete oxidation of CO at120℃, and the corresponding stability measurement performed beyond100h didn’t show any inactivition.(4) TiO2deposited by uniformly dispersed metal particles was prepared through situ redox strategy. Adjusting the types of metals and their content supported on the TiO2indicated that0.51wt%Pt loading led to CO complete conversion at70℃. Further, the promoting role of H2for CO oxidation and corresponding reaction mechanisms in presence of TiO2with and without Pd deposited were discussed.(5)Pd/TiO2/Al2O3composite catalyst was fabricated and the role of light irradiation played in CO coupling catalytic reaction was inspected. All results showed that the synergistic effect of light and heat at region of lower temperature was pretty evident.