The project at hand proposes to develop an advanced electrochemical characterization in-situ water-based TEM (ElWBinsTEM) technique with nanometre resolution. Going beyond the state-of-the-art, this technique will provide at least 10 times higher resolution with a possibility of sub-nanometre resolution. It will enable me to obtain the necessary insights and breakthroughs related to platinum based nanoparticles potential- and time-dependent changes. The results will be beneficial for academia and industry alike in two separate ways: one is the introduction on new technique which will enable the observation of in-situ electrochemical processes like dealloying and degradation and the other one is a deeper understanding of the potential dependent changes occurring on energy conversion materials like platinum nanoparticles. New insights can potentially inspire new concepts for the synthesis of more stable low temperature fuel cell catalysts, resulting in a faster commercialisation of this perspective sustainable technology. The development of ElWBinsTEM technique will provide scientific tool to study also any other energy conversion and storage materials.There is strong scientific evidence that the proposed technique can be successful, due to the fact that sub-nanometre water based in-situ TEM has been recently achieved and that the principle of electrochemical in-situ TEM was already shown, however with relatively poor resolution. In this project, the idea of bringing electrochemical control in to commercial thin-window in-situ TEM cell is coupled with excellent supervision in the fields of applied electrochemistry and in-situ TEM microscopy in an prestigious institution Max-Planck for Iron Research in Düsseldorf, Germany with all the necessary facilities required for the proposed research. The applicant will receive world-class training and expertise which will be a great boost for his European career development.