Catalytic reactions: Single particle spectroscopy

Solid catalysts govern many industrial chemistry reactions, especially electron transfer processes such as the formation of hydrogen from water. However, there is still a lack of a deep understanding of catalytic reactions at the nanometer scale because solid catalysts consist of countless crystals of varying sizes and shapes, leading to heterogeneous reaction rates.
Now, Paul Mulvaney and colleagues1 from the University of Melbourne in Australia have developed a new method that enables the direct observation of chemical reactions on the surfaces of individual gold nanocrystals.
The researchers achieved this breakthrough by exploiting a ten-year old spectroscopy technique—used to correlate the shape and size of metal nanocrystals with their optical properties—for measuring the kinetics of reactions of nanoparticles. In their procedure, the researchers first precisely located and marked individual nanocrystals using a focussed ion beam, and then monitored minute transformations of crystals due to ongoing chemical reactions.