The authors focused their efforts on a Pd2dba3-derived catalyst deposited on graphite and carbon-coated copper grids, as models for Pd/C in the Mizoroki–Heck and Suzuki–Miyaura reactions and in order to perform electron microscopy on the samples. They developed an area search protocol that combined scanning electron microscopy or transmission electron microscopy images from the millimetre to the nanometre scale with computational matching at different reaction times, to monitor the evolution of a group of palladium nanoparticles before and after reaction (pictured). While the nanoparticles seemed to be stable, they also tracked single palladium atoms, and found they had relocated closer to the nanoparticles. This caused the atoms to sinter and merge with the nanoparticles, increasing their size; the authors found this correlated with a decreased activity of the supported catalyst. Whilst such mobility can be thermodynamically explained, taking into consideration the bond strengths of Pd atoms with either
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