Study For Synthesis And Application Of Novel Metal-oxide Heteroaggregate Nanocatalysts

Traditionally, platinum catalysts are prepared by impregnation, ion exchange, coprecipitation,and sol-gel methods, etc. For catalyst prepared by the above mentioned methods, there is noteffective interaction between metals and supports, and thus the prepared platinum catalysts showpoor activity, selectivity, and thermal stability. Currently, reducible oxides supported Pt catalystscan enhance the interaction between metals and supports, and the interface between metals andsupports shows high activity and selectivity for some kinds of reactions. Although these worksenriched the literature database on advanced platinum catalysts, the development of newmethodologies for the design ofhigh activity and selectivityofplatinumcatalysts is stilldesirable.In this work, a new method for preparation of strong metal-support interaction Pt catalystswas developed. PtM （M=Ni, Fe, Co） alloy nanopartilces were synthesized by a liquid phasereduction method employing butyllithium as a reducing agent. The alumina supported PtMmaterials were then used as precursors to obtain the Pt-MxOy/Al₂O₃catalysts through calcination.The influence of synthesis conditions of PtM alloy nanoparticles was surveyed. For the catalytichydrogenation of p-chloronitrobenzene preparation of aniline chloride as the probe reaction, thecatalytic performance of the Pt-MxOy/Al₂O₃catalysts for p-chloronitrobenzene hydrogenationreaction were investigated. The relevant characterizations such as XRD, XPS and TEM wereconducted for PtM alloy nanoparticles and Pt-MxOy/Al₂O₃catalysts, and the result showed that thePtM nanoparticles are uniform alloy. Moreover, compared to PtM alloy nanoparticles, the Ptparticle size of Pt-MxOy/Al₂O₃using PtM alloy nanoparticle precursors did not increase bycalcination, indicating good thermal stability. The catalytic activities of Pt-MxOy/Al₂O₃for p-chloronitrobenzene hydrogenation reaction were significantly higher than that of control Pt/Al₂O₃catalysts due to its strong Pt-MxOyinteraction.