Sintering of Au Particles Supported on TiO2(110) during CO Oxidation
نویسندگان
چکیده
Sintering of supported metal catalysts is of primary interest in heterogeneous catalysis. The presence of reactant gases, especially oxidants, often accelerates the sintering of supported metal catalysts. Our in situ studies using scanning tunneling microscopy (STM) compare the sintering of Au particles supported on TiO2(110) in the presence of CO, O2, or mixtures of the two gases. The results reveal a synergetic effect of CO/O2 mixtures in accelerating the sintering of supported Au particles. By monitoring the morphological changes of individual Au particles, in situ studies allow investigation of the sintering kinetics of Au particles supported on TiO2(110) during CO oxidation. The results support a reactant-induced mechanism and provide a more complete kinetic description of the sintering of supported metal catalysts beyond a mean-field description.
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