Three eyes see more than two
Rupprechter´s group and FHI Berlin succeeded in monitoring a catalytic reaction on a defined catalyst surface with three different microscopies under exactly the same conditions in real time. In this way, information is obtained that none of the methods alone could reveal.
Research teams from the Institute of Materials Chemistry and the Fritz Haber Institute in Berlin have developed a novel approach that allows to have “triple eyes” on a catalytic reaction. It has been possible to combine three different microscopies in a way that the same spot on the same sample was examined under the same environmental conditions, called correlative microscopy. Three different electron microscopies were used: two different variants of photoemission electron microscopy (PEEM), namely UV-PEEM and X-PEEM, and low energy electron microscopy (LEEM). Through the correlative approach, it was possible to effectively use the specific strength of each of the respective microscopy methods (spatial and energy resolution, field of view, magnification down to the nanometer range) and thus to image an ongoing catalytic reaction in unprecedented detail.
This way, they were able to show that during the catalytic conversion of hydrogen and oxygen to water, reaction fronts on the crystal surface not only form remarkable geometric patterns, but also a new mechanism of the propagation of these fronts was discovered. Especially for climate-relevant technologies such as ecologically clean hydrogen-based energy production in fuel cells, a comprehensive understanding of such processes is crucial.