Nanoparticles can be used in many ways as catalysts. To be able to tailor them in such a way that they can catalyse certain reactions selectively and efficiently, researchers need to determine the properties of single particles as precisely as possible. So far, an ensemble of many nanoparticles is analysed. However, the problem of these investigations is that the contributions of different particles interfere, so that the properties of individual particles remain concealed. Researchers at Ruhr-Universiät Bochum in cooperation with colleagues from University of Duisburg-Essen and Technical University of Munich have developed a novel method in order to observe single nanoparticles before, during and after an electrochemical reaction. They depict the process in the journal Angewandte Chemie, published on 16 April 2019.