Research Frank Blockhuys

Abstract

The performance of a material in an application strongly depends on the physical and chemical nature of its surface at the atomic level. Therefore, the modification of surfaces is widely applied in materials research. The interest in efficient modification methods, specifically designed for metal oxides, has grown considerably because the resulting materials are very stable. Grafting of silicon- or phosphorus-containing groups on the surface is a well-known method for such modifications. Using bifunctional reagents changes the way in which the surface-modified material interacts with adsorbates and provides increased adsorption selectivity. Therefore, these hybrid materials are promising candidates for selective metal sorption to extract valuable or hazardous metals from solutions or waste streams. Even though the grafting of metal oxides has become more prevalent in recent years, little is known about the structural characteristics of the organic-inorganic interface and how this relates to the material's selectivity for certain compounds. This project aims at providing insight into the adsorption behaviour of these materials by performing advanced calculations as part of a multidisciplinary study.

Researcher(s)

• Promoter: Blockhuys Frank
• Fellow: Luntadila Lufungula Léon

Research team(s)

Project type(s)

• Research Project

Abstract

The performance of a material in an application strongly depends on the physical and chemical nature of its surface at the atomic level. Therefore, the modification of surfaces is widely applied in materials research. The interest in efficient modification methods, specifically designed for metal oxides, has grown considerably because the resulting materials are very stable. Grafting of silicon- or phosphorus-containing groups on the surface is a well-known method for such modifications. Using bifunctional reagents changes the way in which the surface-modified material interacts with adsorbates and provides increased adsorption selectivity. Therefore, these hybrid materials are promising candidates for selective metal sorption to extract valuable or hazardous metals from solutions or waste streams. Even though the grafting of metal oxides has become more prevalent in recent years, little is known about the structural characteristics of the organic-inorganic interface and how this relates to the material's selectivity for certain compounds. This project aims at providing insight into the adsorption behaviour of these materials by performing advanced calculations as part of a multidisciplinary study.

Researcher(s)

• Promoter: Blockhuys Frank
• Fellow: Luntadila Lufungula Léon

Research team(s)

Project type(s)

• Research Project

Abstract

Organic second-order nonlinear optical (NLO) materials for electro-optical applications are gaining interest because of their superior properties in comparison with their inorganic counterparts. The design and selection of the materials, however, remains a mainly empirical undertaking due to the multi-level nature of this research. Therefore, in this project, both the molecular and supramolecular levels will be optimised for a promising category of compounds, in accordance with a fundamental theory which describes the NLO properties of organic solids. At the molecular level, information on the NLO potential of a molecule is obtained by calculating the hyperpolarizability. The most promising compounds are then synthesized, crystallized and characterized by single-crystal X-ray diffraction (XRD). At the supramolecular level, solid-state calculations under Periodic Boundary Conditions (PBC) are used in a crystal engineering approach to reveal the relative importance of the different supramolecular synthons that contribute to the formation of polar crystal structures: only crystals with polar space groups qualify since the presence of an inversion centre cancels out all secondary NLO effects. In addition, the nonlinear optical susceptibility, the macroscopic counterpart of the hyperpolarizability, can be estimated from the calculations, leading to a fast, pragmatic and cost-efficient selection of superior NLO materials.

Researcher(s)

• Promoter: Blockhuys Frank
• Fellow: Van de Velde Jasper

Research team(s)

Project type(s)

• Research Project

Abstract

Very recently, 3 very active compounds, all with a benzo[j]phenanthridine-7,12-dione skeletal structure, against the causative agent of tuberculosis, Mycobacterium tuberculosis, were discovered. However, since the current syntheses for these compounds are inadequate to prepare sufficient quantities for further biotesting and elucidation of the mechanism of action, a number of new, efficient approaches are presented in this project . Furthermore, it is the intention to develop new syntheses of various substituted benzo[j]phenanthridine-7,12-diones, and to test these compounds for their anti-mycobacterial activiteit with the aim to achieve more active and less toxic analogues.

Researcher(s)

• Promoter: Abbaspour Tehrani Kourosch
• Promoter: Blockhuys Frank
• Fellow: Smets Robert

Research team(s)

• Organic synthesis (ORSY)

Project type(s)

• Research Project

Abstract

This project entails the prediction of the fragmentation pathways and mass spectra of a series of peptides and lipids using quantum chemical calculations at the level of DFT. This will give rise to new insight into the fragmentation behaviour of these compounds, leading to the improvement of the currently available prediction tools, the development of new algorithms (e.g., for more efficient identification of lipids) or the optimization of very specific MS-based assays (e.g., SRM).

Researcher(s)

• Promoter: Blockhuys Frank
• Fellow: Cautereels Julie

Research team(s)

Project type(s)

• Research Project

Abstract

This project aims at elucidating the impact of the grafting methodology and the type of functional organic group on the physico-chemical properties of the obtained organic surface layer and its interaction with probe molecules. To obtain the necessary insights, synthesis and in-depth complementary (in-situ and hyphenated) characterization techniques will be correlated to quantum chemical calculations of large model systems.

Researcher(s)

• Promoter: Meynen Vera
• Co-promoter: Blockhuys Frank

Research team(s)

• Laboratory of adsorption and catalysis (LADCA)

Project type(s)

• Research Project

Abstract

The proposed project studies the upscaling of three reactions for the synthesis of PPV oligomers with proven opto-electronic properties. The goal of the project is to determine, from a process point of view, the most suitable product and synthesis method from three possible candidates. In addition, a method will be optimized to determine heats of reaction based on quantum chemical calculations, and from the calorimetric experiments fundamental insights into the mechanisms of the reactions that will be studied will emerge.

Researcher(s)

• Promoter: Blockhuys Frank
• Co-principal investigator: Vande Velde Christophe

Research team(s)

Project type(s)

• Research Project

Abstract

Molecular design is generally employed to tune interesting molecular properties of oligomers. However, crystal symmetry often prevents the expression of the desired macroscopic properties. An elaborate X-ray diffraction study is carried out to rationalise the crystal packing in terms of intermolecular interactions. The higher goal consists of using these interactions as an instrument to engineer the desired supramolecular structure. This is done by introducing functional groups in the molecular structure. By means of this strategy we will attempt to obtain polar crystals.

Researcher(s)

• Promoter: Blockhuys Frank
• Fellow: Collas Alain

Research team(s)

Project type(s)

• Research Project

Abstract

The further miniaturisation of current memory technology ¿ based on silicon ¿ will become impossible in the near future. A promising alternative is the development of technology based on organic semiconductors. Using an iterative procedure consisting of synthesis and evaluation, the memory properties of three classes of organic compounds (distyrylbenzenes, diphenylcarbodiimides and organometallic oligomers) will be investigated. In the end, this should lead to a superior material and increased insight into the fundamental mechanisms of organic memories.

Researcher(s)

• Promoter: Blockhuys Frank
• Fellow: De Borger Roeland

Research team(s)

Project type(s)

• Research Project

Abstract

Novel conjugated materials, hybrids of organic and inorganic conjugated systems, applicable in semiconductor-based devices such as sensors and organic memories, will be synthesised, characterised using diffraction and spectroscopic techniques, and evaluated as electro-active components in these applications.

Researcher(s)

• Promoter: Blockhuys Frank

Research team(s)

Project type(s)

• Research Project

Abstract

Conjugated organic and organometallic compounds and their stable radicals, useful as organic semiconductors, will be synthesized and characterized using advanced pulse and multi-frequency EPR techniques. The combination with all-electron DFT quantum chemical calculations is essential to extract all available structural information contained in the spectroscopic data.

Researcher(s)

• Promoter: Van Alsenoy Kris
• Co-promoter: Blockhuys Frank
• Co-promoter: Goovaerts Etienne
• Co-promoter: Van Doorslaer Sabine

Research team(s)

Project type(s)

• Research Project

Abstract

Molecular design is generally employed to tune interesting molecular properties of oligomers. However, crystal symmetry often prevents the expression of the desired macroscopic properties. An elaborate X-ray diffraction study is carried out to rationalise the crystal packing in terms of intermolecular interactions. The higher goal consists of using these interactions as an instrument to engineer the desired supramolecular structure. This is done by introducing functional groups in the molecular structure. By means of this strategy we will attempt to obtain polar crystals.

Researcher(s)

• Promoter: Blockhuys Frank
• Fellow: Collas Alain

Research team(s)

Project type(s)

• Research Project

Abstract

The aim of this project is to acquire knowledge of and experience in the use of experimental charge density methods in the field of structural chemistry through original research.

Researcher(s)

• Promoter: Blockhuys Frank
• Fellow: Vande Velde Christophe

Research team(s)

Project type(s)

• Research Project

Abstract

The further miniaturisation of current memory technology ¿ based on silicon ¿ will become impossible in the near future. A promising alternative is the development of technology based on organic semiconductors. Using an iterative procedure consisting of synthesis and evaluation, the memory properties of three classes of organic compounds (distyrylbenzenes, diphenylcarbodiimides and organometallic oligomers) will be investigated. In the end, this should lead to a superior material and increased insight into the fundamental mechanisms of organic memories.

Researcher(s)

• Promoter: Blockhuys Frank
• Fellow: De Borger Roeland

Research team(s)

Project type(s)

• Research Project

Abstract

To stimulate research on the macroscopic or bulk description of sensor materials, in which the microcrystalline layer, of which the bulk properties largely determine the precise activity of the resulting gas sensor, occupies a central position, a consortium of four research groups is created in which expertise in the field of the synthesis of new sensor materials and the electrochemical procedure , which forms the basis of the construction of sensors, is combined with know-how in the field of morphological studies on (organic) materials using nitrogen physisorption methods and electron microscopy, and with expertise in the field of the measurement of phase equilibrium partition coefficients between two phases.

Researcher(s)

• Promoter: Blockhuys Frank
• Co-promoter: Cool Pegie
• Co-promoter: Van Tendeloo Staf

Research team(s)

Project type(s)

• Research Project

Abstract

In this project three novel classes of materials for conductometric gas sensors of which quantum chemical calculations have indicated favourable qualities, such as high stability and good manufacturing properties,will be synthesised and tested in practice. It concerns materials based upon (i) 2,6-diphenyl-1,5-diaza-1,5-dihydro-s-indaceen, (ii) arylenevinylene trimers with N-methylpyrrole as the central ring, and (iii) phenylene-nickel(II) complexes. Several synthetic approaches will be investigated for each of these groups of compounds.

Researcher(s)

• Promoter: Blockhuys Frank
• Co-promoter: Geise Herman
• Fellow: Vande Velde Christophe

Research team(s)

Project type(s)

• Research Project

Abstract

Aiming at new luminescent materials for Organic LEDs emitting in the blue, a number of graftcopolymers will be synthesized and their performances compared with those of blends of luminescent oligomers in a polymer matrix. The graftcopolymers will consist of derivatives of 1,4-bis(2,2-diphenylethenyl)benzene as the chromophores grafted in various percentages onto either a copolymer of vinylbenzylchloride (VBC) and vinylcarbazole or onto a copolymer of VBC and styrene.

Researcher(s)

• Promoter: Blockhuys Frank
• Fellow: Wuyts Cindy

Research team(s)

Project type(s)

• Research Project

Abstract

The project endeavours to provide theoretical support to the experimental research on gas sensors and an electronic nose based on electrically conducting oligomers, which will enable the experimental work to be carried out in a more efficient way. More to the point, this means that a deeper understanding will be sought of the collection of conditions a given oligomer must fulfil to be applied in a gas sensor: these conditions are the stability, ability to be deposited and sensitivity towards molecules in the vapour, of the doped material.

Researcher(s)

• Promoter: Van Alsenoy Kris
• Fellow: Blockhuys Frank

Research team(s)

Project type(s)

• Research Project