Research | Catalyst Diagnostics | Project

Studying the Genesis of Nanobubbles on Zeolite and Metal Organic Framework Thin-Films by Scanning Probe Microscopy

Studying the Genesis of Nanobubbles on Zeolite and Metal Organic Framework Thin-Films by Scanning Probe Microscopy
Joint Doctorate
1st supervisor and 1st promotor: Prof. Bert Weckhuysen (UU)
2nd supervisor and 2nd promotor: Prof. Detlef Lohse (UT)
3rd promotor: Prof. Xuehua Zhang (UT)
Affiliation: Utrecht University and University of Twente
Research theme: Catalyst Diagnostics to Develop More Active Catalysts

Thin-films of porous oxides are interesting to investigate fundamental aspects of diffusion, adsorption and catalysis. In the past years, it has been possible to characterize the formation processes of zeolite and metal organic framework (MOF) thin-films with scanning probe microscopy methods, including liquid-phase Atomic Force Microscopy (AFM) as well as nano-IR-AFM. We wish to build on this expertise and investigate the genesis of nanobubbles at the surface of thin-films of zeolites and MOFs by using liquid-phase AFM as well as Kelvin probe microscopy. The latter method is sensitive to surface potentials, hence provides information on the type of elements, and their coordination.

In a first stage of the project we make use of solvent exchange (ethanol by water) and temperature variations (cold liquid on hot thin-film surface) to induce the local formation of gas bubbles. This will be done for zeolite thin-films in which the Si/Al ratio has been altered. In a second stage of the project, we will make use of MOF thin-films active in (photo-) electrocatalysis and induce the formation of gas bubbles during water splitting. The goal is to correlate surface heterogeneities, as probed with Kelvin probe microscopy, with bubble formation during e.g. solvent exchange and catalysis.

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