In situ experiments to manipulate the atomic structure of nanocrystalline carbon monolayers and Pt-nanoclusters on graphene

Abstract

By observing and manipulating our surroundings, we attempt to explain the universe from the largest to the smallest scale. In that endeavour, high-resolution transmission electron microscopy [HRTEM] opens the way for both observation and manipulation on very small scales. In this work, advanced aberration-correct electron microscopy in the form of the SALVE instrument is used to perform in-situ high-resolution transmission electron microscopy experiments on nanocrystalline graphene (NCG) and Pt-nanoclusters sputtered on a graphene substrate [Pt@SLG]. By merging the TEM’s inherent ability to quickly change the beam flux by spreading and focusing the e-beam, with different available acceleration voltages and local temperature control using MEMS chips, a wide range of parameters are accessible during the experiments. In combination, this is used to investigate the dynamics of these materials under different conditions and explore optimal parameters for their in-situ manipulation. Moreover, neural networks were trained to assist with the evaluation of the enormous amount of data recorded to capture dynamic processes. To best fulfil this task, they were specifically adapted to cope with contamination and illumination gradients.