Dr. Jens Kling
Technical University of Denmark Authors | Jens Kling, Christian D. Damsgaard, Thomas W. Hansen & Jakob B. Wagner. Email | email@example.com
|Application||Quantifying the Growth of Individual Graphene Layers by In Situ Environmental Transmission Electron Microscopy|
|Authors||Jens Kling, Christian D. Damsgaard, Thomas W. Hansen & Jakob B. Wagner.|
|Topic||Catalysis, Chemical Reaction, Kinetics|
Quantifying the Growth of Individual Graphene Layers by In Situ Environmental Transmission Electron Microscopy
ABSTRACT: The bottom-up approach where materials are built atom by atom are becoming more and more common to create next generation of electric and optical devices. For instance, heterostructured semiconductor nanowires, carbon nanotubes and graphene those with excellent electron mobility and band gap structure, are the examples of materials synthesized via a bottom up approach. The atom-by-atom building scheme is highly dependent on synthesis parameters such as temperature, precursors, and time of synthesis. The resulted structures finally determines the macroscopic properties, such as strength, brittleness, electric, magnetic, optical properties and catalytic performance, etc. In order to tailor materials for specific applications, control of the synthesis parameters for obtaining the desired materials structure is necessary.
Achieving in situ TEM observation of chemical synthesis process enables chemical reaction kinetics and mechanisms to be followed at the nanoscale, even at atomic scale. The insights provided by in situ TEM observations can be exploited to facilitate robust scaling of nanoscale synthesis processes to the manufacturing scale
Understanding gas–solid interaction involved in materials synthesis and their functioning is central to the ability to control them. However, it has been clear that measurements performed on reactants and products are often not sufficient to determine the dynamic state of materials/samples ‘in operation’. Therefore, direct observations of chemical reactions down to atomic scale are of utmost importance.
DENSsolutions Heating System provides a unique platform for the detailed study of chemical synthesis/process at environmental TEM (ETEM). DENSsolutions has a fast feedback control system that stabilizes the sample immediately when changing parameters such as pressure and temperature, opening the possibility of HREM imaging of a transient event. Furthermore, the system provides accurate temperature readout at various gas environments (composition & pressure) and even during the change of the environment such that optimization of the growth parameters can be achieved in a reliable and efficient way