News

An international study led by the Chemistry Department at University College London (UCL) in collaboration with the Center for Molecular Modeling (CMM) at Ghent University and the Central Laser Facility (CLF) has made a new and unexpected discovery about industrial catalysts that could help to increase the efficiency of the production of chemical building blocks from non-fossil feedstocks such as methanol. Their findings could lead to a reduction of the cost and environmental impact of the process, making it a viable alternative to fossil fuels.

Methanol conversion towards chemicals of higher energy density is a sustainable alternative to fossil fuels. To spur the chemical reactions needed to turn methanol into complex chains of carbon like gasoline industrial catalysts are used. One of the most popular catalysts are zeolites, which are microporous, crystalline structures made up of silicon, aluminium and oxygen atoms that form a framework of cavities and channels, known as pores. Their structure means they are often referred to as molecular sieves. The stability and efficiency of zeolites is a major concern, as the build-up of carbon deposits tend to block the pores, eventually leading to deactivation of the process. At this point, the zeolite must be replaced or reactivated through an expensive, energy-intensive and environmentally unfriendly industrial process that effectively burns away whatever is hindering the catalytic process. These zeolites are of high value to industry and discovering why zeolites deactivate and precisely when the process starts is of great interest to scientists and to industry.

Researchers at UCL, UGent, and CLF were able to provide answers to these questions by applying Kerr gated Raman spectroscopy in combination with molecular simulations. Raman spectroscopy is one of the most common techniques used to investigate catalysis as it can tell which molecules are present during the reaction. However, it suffers from background fluorescence that easily drowns out the Raman signal of interest. That is where the Kerr gate comes into play. In contrast to Raman fluorescence, which is an instantaneous process, the background fluorescence is delayed by a few picoseconds. The Kerr gate can filter out this unwanted fluorescence leaving scientists with a clear Raman signal to read.

Using Kerr gated Raman spectroscopy the team succeeded to resolve the molecular fingerprints at all stages of the catalytic reaction. To interpret the complex Raman spectra, containing contributions from a lot of different hydrocarbons that were produced during the process, molecular simulations were performed by CMM researchers. The combination of experimental observations and theoretical calculations enabled to pinpoint the presence of important hydrocarbon species during the process. In particular, they were able to identify what sort of hydrocarbon was being formed at the moment the catalyst started to deactivate – like catching a criminal holding a knife at a murder scene, they were able to catch the culprit red handed.

In the past, it had been thought that a species of hydrocarbon called polycyclic aromatics (polyaromatics) were the main deactivating agents, but the new research has shown that this is not the case. In fact, shortly before the polyaromatics are formed, another species called polyenes are formed and, in fact, it is they that are present at the moment the catalyst started to deactivate. This was a completely new and unexpected discovery. ‘I think that this will change the way people think about how these materials deactivate because, as soon as you know who the culprits are, you are able to design a strategy,’ said teamleader Andy Beale of UCL.

There is a huge energy cost, as well as time cost, associated with reactivating catalysts frequently, so anything that can keep catalysts doing their job for longer will save money, energy and reduce the environmental impact – resulting in greener fuels. The study could be significant for industry especially as methanol can be produced from biomass stocks – meaning that gasoline may not have to come from fossil fuel stocks in the future.

The project is an ongoing collaboration between University College London, Ghent University, the Central Laser Facility, and the Catalysis Hub – a consortium created with the aim of establishing a world-leading programme of catalytic science in the UK. The findings have been published in the journal Nature Materials.

Read the article here.

The research group of prof. Van Speybroeck, embedded within the multidisciplinary Center for Molecular Modeling at Ghent University, Belgium (CMM,  http://molmod.ugent.be), is looking for a highly motivated researcher to perform state-of-the-art research in the field of theoretical modeling of catalysis in complex reaction environments. We especially welcome candidates with a strong track record who may become eligible to apply for a prestigious Ph.D. fellowship at our national funding agency (FWO).

More info about the CMM

The CMM groups about 40 researchers of the faculties of Science and Engineering and Architecture with molecular modeling interests and is unique in the university as it clusters researchers with various backgrounds, from various departments and faculties. The CMM aims to model molecules, materials and processes at the nanoscale by bringing together physicists, chemists, (bio-)engineers and stimulating collaborations across disciplines. This multidisciplinary collaborative mission is the DNA of the CMM and key to achieve scientific excellence in the field of molecular modeling.

The CMM focuses on frontier research in six major areas: chemical kinetics in nanoporous materials, computational material research on the nanoscale, spectroscopy, many-particle physics, model development and bio- and organic chemistry. The six areas define the core-business of the main activities, and research in each of them is performed within the frame of a strong network with partners at Ghent University, in Flanders and at an international level. The research of this Ph.D. position is situated in the “Nanoporous Materials” research area, however to pursue excellence we strongly stimulate interactions between the various researchers in our team as well as with our vast network of national and international partners. The research of the CMM is internationally regarded to be at the forefront in its field.

The prospective candidate will join a strongly connected research team and will collaborate with national and international academic partners. He/she will benefit from the experience present in the research group to model chemical transformations at operating conditions. A strong body of expertise was developed in this area in the framework of various ERC grants.

More info about the research topic

This is a position within the framework of a joint Excellence Of Science project (EOS, https://www.fwo.be/en/fellowships-funding/research-projects/eos-research-project/) in collaboration with Prof. Bert Sels (KULeuven), Prof. Bert Maes (UA), Prof. Gwilherm Evano (ULB) and Prof. Christophe Detrembleur (ULiège). In this project named the BioFactory (Understanding and prediction of lignin-derived compound conversion in complex reaction environments for the production of fine chemicals and bio-based polymers) we aim to develop new and green synthetic methodologies for the transformation of the 4-lignin-derived monomers, obtained from an established and efficient lignin-first biorefinery process, into bulk/fine chemicals and polymers. Conversion of non-edible biomass to valuable functionalized chemicals and high-energy density fuels plays an important role in the transition to a non-fossil-based economy. Within this project you will work on modelling activation energies, reactivity patterns and screen for catalysts, ligands and directing groups for C-H and C-O activations. Furthermore, you will be at the front line of unravelling polymerization chemistry of recently developed cyclic(imino)carbonates. Because the scope of the BioFactactory is both to produce platform molecules and to use them for the production of industrially relevant compounds starting from lignin-derived monomers, the problems you will tackle vary both in size and in complexity. Modeling is quintessential to unravel mechanistically the new synthetic routes and optimize selectivities. However, the proposed pathways take place in a complex molecular environment such as hot-pressurized water for the conversion of ferulic acid to bio-catechol (Bomon et al., 2019: https://doi.org/10.1002/anie.201913023). Therefore, you will use a rich plethora of modeling techniques which allow to obtain mechanistic insight at operating conditions, thus at the experimental temperatures and pressures and taking into account realistic solvents. Often we start using density functional theory calculations to gain fundamental understandings of the problems at hand. However, as computational power keeps increasing we are now able to model these systems within a more realistic environment e.g. the solvent environment and/or the realistic catalyst, … To this end free energy profiles can be constructed accounting for the operating conditions, using advanced molecular dynamics methods. Such techniques allow following chemical transformations in-situ, thus closely mimicking the experimental conditions. You will focus mainly on reactions in the field of organic chemistry in a homogeneous environment, ranging from reactions catalysed by organo- and transition-metal catalysts to reactions in complex solvent environments such as hot-pressurized water. Within the project the candidate will work in close collaboration with our experimental partners of the BioFactory project with whom we have already produced high impact publications. Our collaborative efforts within the experimental network, recently gave rise to very high impact papers in the broad field of chemistry (Bomon et al., 2019: https://doi.org/10.1002/anie.201913023; Ouhib et al., 2019: 10.1002/anie.201905969]

Who are we looking for?

We are looking for a highly motivated and creative Ph.D. candidate with:  

• An excellent master’s degree of an international equivalent in the field of Chemistry, Chemical Engineering, Physics, Physical Chemistry or a related field;
• A strong interest in molecular modelling;
• Excellent research and scientific writing skills;
• Perseverance and an independent, pro-active working style;
• The willingness to look beyond the borders of his/her own discipline and a strong motivation to work in a multidisciplinary team;
• Experience with quantum chemistry software (Gaussian, VASP, CP2K,…) and coding (Python, C, ...) is an advantage.
• Excellent collaboration and communication skills (written and verbally) in English

What can we offer you?

The selected candidate will get the ability to strengthen his/her CV within the context of a strongly motivated and multidisciplinary research team and have to ability to contribute to challenging topical research to solve important societal questions. He/she will have the opportunity to attend various international conferences and to include research stays abroad in the most prominent international research teams in this field within the framework of his/her Ph.D. The successful candidate will end up in a University with a strong PhD community that offers a broad range of training possibilities for PhD candidates, both within the research topic and focused on transferrable skills (e.g. time management, presentation skills, leadership, etc.).

How to apply?

It is the intention to fill this position as soon as possible. Students who will obtain their Master degree in June/July are also eligible. For more information on the position or the CMM, candidates can get in touch with Prof. Veronique Van Speybroeck (Veronique.vanspeybroeck@ugent.be).

Interested candidates are requested to prepare the following documents:

1. The filled out application form (see Application-Form.doc)
2. A motivation letter
3. A curriculum vitae
4. Copies of the relevant diplomas and grade lists

All these documents should be send to cmm.vacancies@ugent.be, according to the guidelines mentioned in the application form.

On monday, 25th of November 2019, Prof. Ilja Siepmann will present a lecture entitled Predictive modeling of Adsorption in nanoporous materials: high-throughput screening, machine learning and first principles simulations at CMM in Auditorium A.03 Industrieel Beheer.

J. Ilja Siepmann is a Distinguished McKnight University Professor, a Distinguished Teaching Professor, and member of the graduate faculties in chemistry, chemical physics, chemical engineering, and materials science at the University of Minnesota. He is also the director of the DOE-funded Nanoporous Materials Genome Center and an associate editor for the Journal of Chemical and Engineering Data. He received his Ph.D. in Chemistry from the University of Cambridge. Before joining the University of Minnesota in 1994, Dr. Siepmann carried out postdoctoral research at the IBM Zurich Research Laboratory, the Royal/Shell Laboratory in Amsterdam, and the University of Pennsylvania's Laboratory for the Research on the Structure of Matter. His scientific interests are focused on particle-based simulations of complex chemical systems, including the prediction of phase and sorption equilibria and of thermophysical properties, the understanding of retention in chromatography, and the investigation of microheterogeneous fluids and nucleation phenomena. His research efforts have advanced the capabilities of molecular simulations through the development of efficient Monte Carlo algorithms and transferable force fields

PhD position available in the field of "thermodynamic modeling of adsorption in flexible nanoporous materials” under the supervision of prof. L. Vanduyfhuys at the Center for Molecular Modeling, Ghent University, Belgium.

The multidisciplinary Center for Molecular Modeling (CMM, http://molmod.ugent.be), is looking for a highly motivated researcher to perform state-of-the-art research in the field of thermodynamic modeling of adsorption in nanoporous materials. We especially welcome highly motivated candidates with a strong track record who may become eligible to apply for a prestigious PhD fellowships at our national funding agency (FWO).

Thermodynamics may be regarded as one of the most widely applied branches of physics, interwoven in many aspects of life on our planet. Although it was originally developed mainly to increase the efficiency of steam engines, its applications have evolved greatly and now include a description of chemical reactions, physical and chemical equilibria. Statistical thermodynamics is a particularly interesting extension of thermodynamics, where one tries to understand the thermodynamics of macroscopic systems from a statistical description of the microscopically accessible states. The application of statistical physics can be used to make the bridge between the output of molecular simulations such as molecular dynamics and Monte Carlo on the one hand, and the thermodynamic observables we can measure macroscopically on the other hand. In this PhD, it is the intention to apply the principles from thermodynamics and statistical physics to investigate the behaviour of a new class of nanoporous materials, i.e. soft porous crystals (SPCs). Some metal organic frameworks (MOFs) are an example of such SPCs. These MOFs are hybrid materials made up from metal ions or metal clusters linked together by organic linkers. It was discovered that some MOFs show “flexible” behavior in the sense that they are capable of transforming between various phases accompanied by substantial changes in the unit cell volume (up to 40%) while retaining their structural integrity. Such transformations can be instigated by various triggers such as mechanical pressure, temperature as well as adsorption of guest molecules.

The goal of this PhD research is to develop mathematical models for the thermodynamic potential of guest-loaded nanoporous materials as function of temperature, pressure and chemical potential in various ensembles (eg. the canonical and the grand canonical ensemble). To obtain the required information for the construction of these models, the candidate will perform various molecular simulations such as molecular dynamics (MD), Monte Carlo (MC) and classical density functional theory (cDFT). Furthermore, it also intended to implement the resulting thermodynamic models in a user-friendly program package to allow for an easy application of the models.

The prospective candidate will join a strongly connected research team and will collaborate with national and international academic partners. He/she will benefit from the experience present in the Center for Molecular Modeling (CMM), specifically on performing advanced molecular simulations and the development of general procedures to model physical transformations in nanoporous materials, as well as its implementation in dedicated software packages. The CMM is an interfaculty research unit at Ghent University headed by Prof. Van Speybroeck, grouping about 40 scientists from the Faculty of Science and the Faculty of Engineering and Architecture. The research team consists of various junior and senior researchers with various backgrounds which enables us to provide a proper intellectual environment for the conducted research. The CMM performs interdisciplinary research at the crossroads between physics, chemistry and materials engineering with the aim to design molecules, materials, and processes at the nanoscale. To this end, the CMM consists of six synergetic research areas: “Nanoporous materials”, “Solid-state physics”, “Bio/organic chemistry”, “Model and software development”, “Spectroscopy”, and “Many-particle physics”. The research of this PhD situates mainly in the areas “Nanoporous materials” and “Model and software development”, but to enable groundbreaking research at the interface of physics, chemistry, and materials science, we strongly stimulate interactions between the various researchers of all areas as well as with the vast network of national and international partners. The CMM is internationally regarded to be at the forefront in its field.  

Who are we looking for?

We are looking for a highly motivated and creative PhD candidate with:

• A master’s degree of a university or international equivalent in the field of Physics, Engineering Physics, Physical Chemistry or a related field;
• Perseverance and an independent, pro-active working style;
• The willingness to look beyond the borders of his/her own discipline and a strong motivation to work in a multidisciplinary team;
• Experience in coding (Python, C, ...) is an advantage. At the very least, the candidate must be willing to learn these skills during the first year of the PhD.
• Excellent collaboration and communication skills (written and verbally) in English.

What can we offer you?

The selected candidate will have the opportunity to attend various international conferences and to include research stays abroad in the some of the most prominent international research teams in this field within the framework of his/her PhD. He/she will get the ability to strengthen his/her CV within the context of a strongly motivated and multidisciplinary research team.

How to apply?

It is the intention to fill this position as soon as possible. Fill in the application form (in attachment) and send the form together with all required documents to prof. Louis Vanduyfhuys (louis.vanduyfhuys@ugent.be) and to cmm.vacancies@ugent.be, mentioning “Vacancy PhD position in the field of thermodynamic modeling of adsorption in nanoporous materials” in the subject of your e-mail.