Currently the following calls for MSc projects are open. If you are interested submit your request via the online form linked to here. First please consult our page information for students.
Supervisor: Jan den Hollander
Title: Investigating Nanoparticle Dispersion of Washcoated Monolith Cores using Diffuse Reflectance Infrared Fourier Transform Spectroscopy during CO Oxidation
Earliest start: 2nd period
Description: Cordierite monoliths washcoated with a Pt/Al2O3 layer are often the catalyst materials of choice in automotive catalysis1. Their function is to reduce pollution from exhaust gas emissions, for instance by CO oxidation to CO2. During operation, the surface of the washcoat changes due to rapid cycling between reducing and oxidizing atmospheres, which is often characterized by metal sintering and can cause deactivation of the catalyst materials2. Using IR spectroscopy, CO can be used as a probe molecule to gain information (a.o., dispersion, facets, and particle size) about the surface metal nanoparticles3. In this research, we will use the analytical technique of Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) to gain information about the metal dispersion in Pt/Al2O3 washcoated monoliths during CO oxidation4. Different aging procedures will also be employed to alter the monolithic substrates thereby influencing the metal nanoparticle dispersion as well as the pore sizes and related pore connectivity.
1. Williams, J. L., Catal. Today 69, 3–9 (2001).
2. Yang, J., Tschamber, V., Habermacher, D., Garin, F. & Gilot, P., Appl. Catal. B Environ. 83, 229–239 (2008).
3. Lepage, M. et al., J. Phys. Chem. C 112, 9394–9404 (2008).
4.Hazlett, M. J. & Epling, W. S., Catal. Today 267, 157–166 (2016).
Supervisor(s): Nicolette Maaskant
Title: The mechanism behind photo-assisted catalysis for CO2 hydrogenation over cobalt based catalysts.
Please note: The project is only available as a fulltime project and needs to start in the second period at the latest, due to availability of supervisor
Description: To create a circular CO2 economy and a more sustainable society efficient CO2 valorisation is necessary. CO2 hydrogenation is an established strategy for converting CO2 into base chemicals, such as hydrocarbons or alcohols. However, typical base metal catalysts for CO2hydrogenation suffer from low activity.1 One approach for improvement is the use of light during thermal catalysis to improve the catalytic process (i.e. photo-assisted catalysis).2 Various photo-assisted reaction pathways are reported, e.g. plasmon band excitation, photothermal effects, excitation of adsorbates and excitation of valence band electrons to the conduction band (Figure 1A).2–4 To fully take advantage of photo-assisted catalysis, a thorough understanding of the interplay between the photons, electrons and the reaction mechanism is needed.
To investigate photo-assisted catalysis, we use catalysts with cobalt nanoparticles supported on TiO2 as it is known to be active for CO2 hydrogenation.5 Using a variety of techniques, like operando infrared spectroscopy and x-ray absorption spectroscopy we have observed that CO2conversion, the reaction intermediates and the oxidation state of cobalt are influenced by shining light on the catalyst during reaction. To further understand the underlying mechanisms of these effects, we want to extend this investigation to different support materials (e.g. silica which is photochemically inert). This will give us more information about the role of the support in the photo-assisted CO2 hydrogenation. During this project you will synthesize some catalyst materials and thoroughly investigate their (catalytic) properties under the influence of light. Techniques that you will use include UV-vis spectroscopy, (operando) infrared spectroscopy and characterisation techniques (e.g. XRD).
1. Vogt, C., Monai, M., Kramer, G. J. & Weckhuysen, B. M. The renaissance of the Sabatier reaction and its applications on Earth and in space. Nat. Catal. 2, 188–197 (2019).
2. Kim, C. et al. Energy-efficient CO2 hydrogenation with fast response using photoexcitation of CO2 adsorbed on metal catalysts. Nat. Commun. 9, 3027 (2018).
3. Xie, B. et al. Synergistic ultraviolet and visible light photo-activation enables intensified low-temperature methanol synthesis over copper/zinc oxide/alumina. Nat. Commun. 11, 1615 (2020).
4. Tan, T. H. et al. Unlocking the potential of the formate pathway in the photo-assisted Sabatier reaction. Nat. Catal. 3, 1034–1043 (2020).
5. Have, I. C. ten et al. Uncovering the reaction mechanism behind CoO as active phase for CO2 hydrogenation. Nat. Commun. 13, 342 (2022).
Supervisor(s): Sophie van Vreeswijk
Title: Synthesis and characterisation of metallocene-based depolymerization catalysts
Earliest start: immediately
Description: Recent research has shown that metallocene catalysts, predominantly used as polymerisation catalysts, can also be applied for the reversed process, namely, the depolymerisation via hydrogenolysis.[1] The advantage of this hydrogenolysis process is that it happens at rather mild conditions (150-200°C and 2 atm H2). In this project, these supported metallocene catalysts will be synthesised, characterised and tested on their performance to depolymerise different types of plastic materials. Typical analytical methods that will be applied are Pyridine-IR, CO-IR, N2 physisorption, UV-vis spectroscopy, Raman spectroscopy and SEM-EDX.
[1] A. H. Mason, A. Motta, A. Das, Q. Ma, M. J. Bedzyk, Y. Kratish and T. J. Marks, Nat Commun 2022, 13, 7187
Supervisor(s): Sophie van Vreeswijk
Title: Depolymerisation kinetics in the hydrogenolysis reaction using metallocene-based catalysts
Earliest start: period 3
Description: Recent research has shown that metallocene catalysts, predominantly used as polymerisation catalysts, can also be applied for the reversed process, namely, the depolymerisation via hydrogenolysis.[1] The advantage of this hydrogenolysis process is that it happens at rather mild conditions (150-200°C and 2 atm H2). In this project, the depolymerisation kinetics of the hydrogenolysis reaction (using metallocene-based catalysts) will be analysed by means of in-situ DRIFT spectroscopy. Different catalysts will be tested on their depolymerisation performance of different types of polymer materials.
[1] A. H. Mason, A. Motta, A. Das, Q. Ma, M. J. Bedzyk, Y. Kratish and T. J. Marks, Nat Commun 2022, 13, 7187.