A5043790461- Zeolite Catalysis and Synthesis
- Metal-Organic Frameworks: Synthesis and Applications
- Mesoporous Materials and Catalysis
- Advanced NMR Techniques and Applications
- Chemical Synthesis and Characterization
- NMR spectroscopy and applications
- Radioactive element chemistry and processing
- Catalysis and Oxidation Reactions
- Polyoxometalates: Synthesis and Applications
- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Covalent Organic Framework Applications
- Catalytic Processes in Materials Science
- Methane Hydrates and Related Phenomena
- Solid-state spectroscopy and crystallography
- Layered Double Hydroxides Synthesis and Applications
- Metal Extraction and Bioleaching
- Mineralogy and Gemology Studies
- Lanthanide and Transition Metal Complexes
- Ionic liquids properties and applications
- Coal and Its By-products
- Food composition and properties
- Selenium in Biological Systems
- X-ray Spectroscopy and Fluorescence Analysis
- Clay minerals and soil interactions
KU Leuven
2016-2025
Institute of Catalysis and Petrochemistry
2014-2025
University of Wisconsin–Madison
2023
Energy Center of Wisconsin
2023
VIB-KU Leuven Center for Microbiology
2023
National High Magnetic Field Laboratory
2022-2023
Max Planck Institute for the Structure and Dynamics of Matter
2015
Max Planck Society
2015
Helmholtz-Zentrum Dresden-Rossendorf
2010
Photocatalytic reduction of molecular oxygen is a promising route toward sustainable production hydrogen peroxide (H2O2). This challenging process requires photoactive semiconductors enabling solar energy driven generation and separation electrons holes with high charge transfer kinetics. Covalent organic frameworks (COFs) are an emerging class semiconductors, tunable at level for carrier transfer. Herein, we report two newly designed two-dimensional COFs based on (diarylamino)benzene linker...
Extensive research has been carried on the molecular adsorption in high surface area materials such as carbonaceous and MOFs well atomic bonded hydrogen metals alloys. Clathrates stand among ones to be recently suggested for storage. Although, simulations predict lower capacity than expected by DOE norms, additional benefits of clathrates low production operational cost, fully reversible reaction, environmentally benign nature, risk flammability make them one most promising explored next...
A highly active Sn site with Lewis acid properties is identified in post-synthetically synthesized Sn/DeAlβ catalyst, prepared by liquid-phase grafting of a dealuminated β-zeolite. Though apparently similar active-site structures have been reported for the post-synthetic and conventional hydrothermal Snβ, detailed study electronic structure redox behavior EXAFS, XANES, DR UV–vis, TPR clearly reveals dissimilarities geometry properties. model proposed using contemporary interpretation...
Nucleation, the pivotal first step of crystallization, governs essential characteristics crystallization products, including size distribution, morphology, and polymorphism. While understanding this process is paramount to design chemical, pharmaceutical, industrial production processes, major knowledge gaps remain, especially with respect porous solids. Also for nanocrystalline ZIF-8, one most widely studied metal–organic frameworks, questions regarding species involved in nucleation...
Abstract The molecular steps involved in the self‐assembly of Cu 3 (BTC) 2 (BTC=1,3,5‐benzenetricarboxylic acid) metal–organic frameworks that enclose Keggin‐type H PW 12 O 40 heteropolyacid molecules were unraveled by using solution 17 O, 31 P, and 183 W NMR spectroscopy, small‐angle X‐ray scattering, near‐IR dynamic light scattering. In aqueous solution, complexation 2+ ions with heteropolyacids was observed. are arranged around Keggin structure so linking through benzenetricarboxylate...
Cu(3)(BTC)(2) with an incorporated Keggin polyoxometalate was demonstrated to be stable under steaming conditions up 483 K, while the isostructural HKUST-1 degrades and transforms into [Cu(2)OH(BTC)(H(2)O)](n)·2nH(2)O from 343 K onwards.
Exposure of faujasite zeolites to different alkali hydroxide solutions readily yields with ABW, CHA, MER and ANA topologies. In NaOH persisted. Aside from new opportunities for zeolite synthesis, this reveals that a suitable aluminosilicate connectivity in the source material significantly facilitates crystallization.
Framework deformation, driven by the cations in channels, determines CO<sub>2</sub> ad- and desorption behavior of zeolites. This allows to tune zeolite properties efficient temperature swing adsorption processes.
The solid-phase Se speciation after short-term (3 weeks) contact of selenite [Se(IV)] oxyanions with pyrite (FeS2) and troilite (FeS) was investigated using X-ray absorption spectroscopy (XAS; near-edge spectroscopy-extended fine structure (XANES-EXAFS)). It found that the nature sulfide mineral dictates final since respectively Se(0) FeSe(x) were formed, meaning reaction mechanism is different these phases cannot be regarded as geochemically similar. experimental results support previously...
A new ordered mesoporous silica material (COK-19) with cubic symmetry is synthesized by silicate polycondensation in a citric acid/citrate buffered micellar solution of Pluronic F127 triblock copolymer near neutral pH. SAXS, nitrogen adsorption, TEM, and electron tomography reveal the final has close packed (Fm3̅m) isolated spherical mesopores interconnected through micropores. Heating synthesis medium from room temperature to 70 °C results mesopore size increase 7.0 11.2 nm. Stepwise...
Using hydrated silicate ionic liquids, phase selection and framework silicon-to-aluminum ratio during inorganic zeolite synthesis were studied as a function of batch composition. Consisting homogeneous single phasic this concept allows careful control crystallization parameters evaluation yield sample homogeneity. Ternary diagrams constructed for syntheses at 90 °C 1 week. The results reveal cation-dependent continuous relation between stoichiometry aluminum content, valid across the...
A well-defined silica nanoparticle model system was developed to study the effect of size and structure aggregates on their membranolytic activity. The were stable characterized using transmission electron microscopy, dynamic light scattering, nitrogen adsorption, small-angle X-ray infrared spectroscopy, paramagnetic resonance. Human red blood cells used for assessing activity aggregates. We found a decreasing hemolytic increasing hydrodynamic diameter aggregates, in contrast trends observed...
Current nucleation models propose manifold options for the formation of crystalline materials. Exploring and distinguishing between different crystallization pathways on molecular level however remain a challenge, especially complex porous These usually consist large unit cells with an ordered framework pore components often nucleate in complex, multiphasic synthesis media, restricting in-depth characterization. This work shows how aluminosilicate speciation during can be documented detail...
A guideline for zeolite phase selection in inorganic synthesis media is proposed, based on a systematic exploration of from using liquid Na+, K+, and Cs+ aluminosilicate. Although the Si/Al ratio zeolites continuous function conditions, boundaries between topologies are sharp. The here-derived criterion relates obtained topology to imposed by medium. For given ratio, framework with highest occupation topologically available cation sites favored. large number published syntheses supporting...
Biomethane is a renewable natural gas substitute produced from biogas. Storage of this sustainable energy vector in confined clathrate hydrates, encapsulated the pores host material, highly promising avenue to improve storage capacity and efficiency. Herein, new type periodic mesoporous organosilica (PMO) nanotubes, referred as hollow ring PMO (HR-PMO), capable promoting methane hydrate formation under mild working conditions (273 K, 3.5 MPa) at high water loading (5.1 g water/g HR-PMO)...
Spherosilicate, consisting of a double 4-ring cyclosilicate core (D4R; Si8O20) with every corner functionalized dimethylsilyl chloride group (-SiMe2Cl), was used as node to construct an isoreticular series porous expanded network materials. Interconnecting the nodes linear, aliphatic α,ω-alkanediol linker molecules yields PolySilicate Porous Organic Polymers (PSiPOPs), new type ordered reticular material related well-known metal–organic and covalent organic frameworks (MOFs COFs). In...
Safe storage and utilisation of hydrogen is an ongoing area research, showing potential to enable becoming effective fuel, substituting current carbon-based sources. Hydrogen associated with a high energy cost due its low density boiling point, which drives price. Clathrates (gas hydrates) are water-based (ice-like) structures incorporating small non-polar compounds such as H
This work describes the synthesis of ordered 3D siloxane-silsesquioxane reticular materials with silicate D4R cubes (Si8O208−), harvested from a sacrificial tetrabutylammonium cyclosilicate hydrate (TBA-CySH) precursor, interlinked octyl and dicyclopentyl (Cp2) hydrocarbon functionalities in one-step organodichlorosilanes. Advanced solid-state NMR spectroscopy allowed us to unravel molecular order nodes their interconnection by silicone linkers. In case octyl-methyl linkers, changing...
A simple and robust high-pressure cell designed for in situ transmission X-ray crystallization studies is presented. The performance of the small/wide-angle scattering experiments microscopy imaging demonstrated zeolite from highly alkaline hydrated silicate ionic liquids at 500 K 150 bar N 2 pressure. design combination with commercial finger-tight connections allows convenient sample loading powders, gases. can be used dead-end or flow-through mode pressurized gases via standard...
New mechanochemical preparations of three multicomponent crystals (MCCs) the form M Cl:urea· x H 2 O ( = Li, Na and Cs) are reported. Their structures were determined by an NMR crystallography approach, combining Rietveld refinement synchrotron powder X-ray diffraction data (PXRD), multinuclear 35 Cl, 7 23 133 solid-state (SSNMR) spectroscopy thermal analysis. The syntheses MCCs, two which novel, optimized for maximum yield efficiency. Cl SSNMR is well suited structural characterization...