Amazing stuff!
"Researchers in Japan have developed a way to count the charge on a single nanoparticle. The technique is accurate down to a single electron, and could offer new insights into fundamental aspects of heterogeneous catalysis.
Many heterogeneous catalysts are composed of metal nanoparticles supported on a metal oxide surface. But interactions between the particle and the support structure can affect the material’s catalytic properties, for example charge transfer from the support to the nanoparticle can alter the way in which substrate molecules interact with the catalyst. ..."
From the abstract:
"A goal in the characterization of supported metal catalysts is to achieve particle-by-particle analysis of the charge state strongly correlated with the catalytic activity. Here, we demonstrate the direct identification of the charge state of individual platinum nanoparticles (NPs) supported on titanium dioxide using ultrahigh sensitivity and precision electron holography. Sophisticated phase-shift analysis for the part of the NPs protruding into the vacuum visualized slight potential changes around individual platinum NPs. The analysis revealed the number (only one to six electrons) and sense (positive or negative) of the charge per platinum NP. The underlying mechanism of platinum charging is explained by the work function differences between platinum and titanium dioxide (depending on the orientation relationship and lattice distortion) and by first-principles calculations in terms of the charge transfer processes."
Counting charges per metal nanoparticle (no public access) Charges on a metal nanoparticle are measured with precision by electron holography
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