Atomic Force Microscope with temperature control up to 300 °C and liquid cell

• Subject Area: Process Engineering, Technical Chemistry
• Term: Funded in 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 552804047

A competitive atomic force microscope (AFM) is being applied for as a replacement for the atomic force microscope that has been used intensively since 2009. The AFM belongs to the class of scanning probe microscopes and is able to characterise a variety of different surfaces with regard to their topography and/or the interaction of a probe with this surface. Surfaces are defined as interfaces between different phases: solid-liquid, solid-gaseous, liquid-liquid, liquid-gaseous or gaseous-liquid. In addition to various imaging modes, such as contact (C)-AFM, non-contact (NC)/tapping AFM, phase contrast (PC)-AFM or lateral force microscopy (LFM), spectroscopic methods such as force spectroscopy are also available, which make it possible to quantify van der Waals, electrostatic, magnetic and interfacial forces. Previous research using atomic force microscopy is to be continued with the proposed AFM and expanded with additional measurement modes. The focus will be on investigations into the morphology of particles and agglomerates. In combination with other imaging techniques, such as optical, electron and X-ray microscopy, a multiscale description of particle surfaces is also possible. Another focus of the work is the interaction of particles with gas-liquid interfaces, i.e. particle-bubble interactions and the associated capillary interactions. The aim of process engineering research is always to transfer the behavior of the individual particle to the processes of mechanical process engineering, such as comminution, coating technology, (high-energy) mixing, flotation, filtration or recycling. The planned AFM extends the previous measuring range by a significantly larger XY and Z travel of the piezo actuator, which makes it possible to characterize larger individual particles and agglomerates. Likewise, measurements with high reaction forces, e.g. particle-particle, particle-bubble, particle-droplet interactions, require a large travel distance in order to be able to record high adhesion forces with a moderate spring constant of the cantilever (or the elastic overall system). New methods such as magnetic force microscopy or Kelvin probe force AFM, which are to be used to characterize hetero-aggregates, will also be possible for the first time with the proposed device. The measurements in fluids will also be expanded to include an electrochemistry option, for example to investigate leaching or oxidation processes and their influence on the surface topology or wetting properties. A special heating cell will make it possible for the first time to investigate particle-particle interactions up to 275 °C and thus quantify the effects of deformation and sintering mechanisms in terms of process engineering.

• DFG Programme: Major Research Instrumentation
• Major Instrumentation: Rasterkraftmikroskop temperierbar bis 300 ° C mit Flüssigkeitsmesszelle
• Instrumentation Group: 5091 Rasterkraft-Mikroskope
• Applicant Institution: Technische Universität Bergakademie Freiberg
• Leader: Professor Dr.-Ing. Urs Peuker