Nature of Au Active Site

Even over the same support and using the same preparation method of deposition-precipitation, the results do not support an unequivocal optimal Au particle size. Bamwenda et al. [20] prepared a series of Au/Ti02 catalysts using the deposition-precipitation method. Their mean Au particle diameters and kinetic parameters of CO oxidation are shown in Table 1. 

A plot of TOF at 300 K versus average Au diameter appears to suggest that there is a dramatic dependence on the Au particle size, with a sharp maximum at around 2.9 nm. However, since the apparent activation energy are different for different samples, the activity of the 2.5 nm sample became similar to the 2.9 nm 

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