SiO2 nanoparticles have been synthesized by combining Stober’s method and nonsurfactant process. The diameters and pore sizes can be controlled by altering the template and its concentration. Mesoporous SiO2 obtained this way has extremely large surface area compared with most oxide supports, which benefits the catalytic performance. Pt nanoparticles were in situ grown on and in mesoporous SiO2 nanoparticles with low amount of the metal and high load ratio. Furthermore, we firstly developed a novel route, called “one-pot” method, to prepare Pt/SiO2 catalyst where mesoporous silica preparing and Pt loading occurred in one step. This method is more efficient in saving reagent, since it can prevent Pt loss. In the meantime, it enables the template to reduce agent. The catalytic activity of Pt/SiO2 samples was measured by CO oxidation. It is indicated that the supporting silica with mesopores is more active than silica with micropores. 1. Introduction With the acceleration of industrialization and the increase of pollution, new catalysts development becomes very important. It is especially true when it comes to catalysts used to process gases from the incomplete combustion [1]. The incomplete combustion occurs in gasoline engine mainly discharges three kinds of harmful emissions: carbon monoxide (CO), unburned hydrocarbon emissions, and nitrogen oxides (NOx) [2]. With the establishment of stricter exhaust standards, together with the limit reserves and high cost of rare metals, preparing efficient catalyst with trace rare metals becomes the focus of study [3]. Three-way catalysis (TWC) which is a revolution can simultaneously converse the three major emissions into CO2, H2O, and N2. The active substance of TWC is usually made of Pt, Pd, and Rh loaded on oxide supporting [2]. Recently, many researches have been developed around oxide supporting such as ceria, zirconia, alumina, and composite ceria-zirconia supporting [4–11]. Silica has also been used for supporting noble metals. For example, mixed oxide catalysts silica-ceria have been prepared through coprecipitation after hydrothermal synthesis for reduction and oxygen storage. The noble metals were loaded after calcination of the supports. The catalyst was fairly active. The full CO oxidation conversion was about 400°C, and the calcination limited the oxygen storage [12]. Also the catalytic performances of noble metals supported on mesoporous silica MCM-41 were investigated for the hydrodesulfurization of benzothiophene. MCM-41 was made by the surfactant method and had been treated at a very high
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