A5085136778- Advanced NMR Techniques and Applications
- Advanced Battery Materials and Technologies
- Solid-state spectroscopy and crystallography
- Advancements in Battery Materials
- X-ray Diffraction in Crystallography
- Zeolite Catalysis and Synthesis
- Crystallization and Solubility Studies
- NMR spectroscopy and applications
- Chemical Synthesis and Characterization
- Metal-Organic Frameworks: Synthesis and Applications
- Muon and positron interactions and applications
- Covalent Organic Framework Applications
- Mesoporous Materials and Catalysis
- Catalysis and Oxidation Reactions
- Catalytic Processes in Materials Science
- Methane Hydrates and Related Phenomena
- Carbon Dioxide Capture Technologies
- Ammonia Synthesis and Nitrogen Reduction
- Blood properties and coagulation
- Thermal Expansion and Ionic Conductivity
- Hemoglobin structure and function
- Hydrogen Storage and Materials
- Advanced Photocatalysis Techniques
- Microfluidic and Capillary Electrophoresis Applications
- Ionic liquids properties and applications
KU Leuven
2018-2025
Institute of Catalysis and Petrochemistry
2018-2025
University of Wisconsin–Madison
2023
Energy Center of Wisconsin
2023
Leibniz University Hannover
2015-2018
Max Planck Institute for Solid State Research
2009-2015
Radboud University Nijmegen
2014
Max Planck Society
2009-2011
Martin Luther University Halle-Wittenberg
2008-2009
Al-contaminated Ta-substituted Li7La3Zr2O12 (LLZ:Ta), synthesized via solid-state reaction, and Al-free Li7La3Zr2O12, fabricated by hot-press sintering (HP-LLZ:Ta), have relative densities of 92.7% 99.0%, respectively. Impedance spectra show the total conductivity LLZ:Ta to be 0.71 mS cm–1 at 30 °C that HP-LLZ:Ta 1.18 cm–1. The lower for than was attributed higher grain boundary resistance density LLZ:Ta, as confirmed their microstructures. Constant direct current measurements with a 0.5 mA...
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...
In nature, tiny amounts of inorganic impurities, such as metals, are incorporated in the protein structures some biomaterials and lead to unusual mechanical properties those materials. A desire produce these biomimicking new materials has stimulated scientists, diverse approaches have been attempted. contrast, research improve themselves by direct metal incorporation into inner rarely tried because difficulty developing a method that can infiltrate metals biomaterials, resulting...
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...
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 local structure and mobility of lithium ions the NASICON-type ionic conductor Li1+xAlxTi2–x(PO4)3 (with x = 0.0, 0.1, 0.2, 0.35, 0.5, 0.7 1.0), synthesized using conventional solid-state reaction route have been studied with nuclear magnetic resonance (NMR) techniques. 6Li, 7Li, 27Al, 31P NMR experiments employed to trace structural changes varying cation concentration. evolution creation new Al P environments changing contents were by magic-angle spinning (MAS) measurements. 6Li MAS...
Abstract Recently, a pulse scheme for heteronuclear spin decoupling in solid‐state NMR, called swept‐frequency two‐pulse phase modulation (SW f ‐TPPM), was introduced which outperforms the standard TPPM and small incremental alteration (SPINAL) schemes. It has also been shown that frequency‐sweep profile can be varied to achieve optimal efficiency crystalline liquid‐crystalline samples, respectively. Here we present detailed comparison of proton performance SW ‐TPPM sequences with tangential...
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...
Oxygen-containing yttrium hydride thin films show a unique reversible change in optical properties as result of illumination. In this article, different solid-state NMR methods are used to follow the changes during such photochromic process. The novel stripline probe technology provides high sensitivity for experiments on film samples with thickness approximately 1 μm. A key observation is that these spectral evidence highly mobile hydrogen species, which disappears upon illumination white...
A "job-sharing" hydrogen storage mechanism is proposed and experimentally investigated in Ru/Li2O nanocomposites which H+ accommodated on the Li2O side, while H– or e– stored side of Ru. Thermal desorption-mass spectroscopy results show that after loading with D2, exhibits an extra desorption peak, contrast to Ru nanoparticles ball-milled alone, indicating a synergistic effect due presence both phases. By varying ratio two phases, it shown increases monotonically area heterojunctions,...
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...
Upon liquid phase adsorption of C1-C5 primary alcohols on high silica MFI zeolites (Si/Al = 11.5-140), the concentration adsorbed molecules largely exceeds traditional sites: Brønsted acid and defect sites. Combining quantitative in situ1H MAS NMR, qualitative multinuclear NMR IR spectroscopy, hydrogen bonding alcohol function to oxygen atoms zeolite siloxane bridges (Si-O-Si) was shown drive additional adsorption. This mechanism co-exists with chemi- physi-sorption sites does not exclude...
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...
Abstract Aluminium carbide, Al 4 C 3 , was characterised by 13 and 27 solid‐state NMR spectroscopy. The spectra display two resonances with an intensity ratio of 1:2, which is in agreement the reported crystal structure. under both static MAS conditions were deconvoluted into spectral components, belonging to aluminium species Al1 Al2 structure . fit allowed for determination relatively large quadrupolar coupling constants ( χ ≈︁ 16 MHz) species. One displayed a tendency having slightly...
Carbon black is chemically modified by selective photocatalytic oxidation, removing amorphous carbon and functionalizing the graphitic fraction to produce porous, graphitized black, commonly used as an adsorbent in chromatography. In contrast pyrolytic treatments, this modification proceeds under mild reaction conditions using oxygen, nitric oxide, water vapor a titanium dioxide photocatalyst at 150 °C. The photo-oxidation can be performed both with close proximity (contact mode) or...
NMR-crystallography, combining advanced NMR, diffraction and molecular modelling reveals a zundel based super-ion to template hydroxysodalite.
Introduction of a dielectric material in nuclear magnetic resonance (NMR) probe head modifies the frequency response circuit, phenomenon revealed by detuning probe. For NMR spectroscopy, this is corrected for tuning and matching prior to measurement. The magnitude detuning, "the shift", provides direct access properties sample, enabling spectrometers simultaneously perform both spectroscopy. By measuring sample permittivity as function frequency, spectroscopy can be performed using new...
This perspective outlines recent developments in the field of NMR spectroscopy, enabling new opportunities for situ studies on bulk and confined clathrate hydrates. These hydrates are crystalline ice-like materials, built up from hydrogen-bonded water molecules, forming cages occluding non-polar gaseous guest including CH
Abstract This article reports on Li self-diffusion in lithium containing metal oxide compounds. Case studies LiNbO 3 , NbO 4 LiTaO LiAlO 2 and LiGaO are presented. The focus is slow diffusion processes the nanometer scale investigated by macroscopic tracer methods (secondary ion mass spectrometry, neutron reflectometry) microscopic (nuclear magnetic resonance spectroscopy, conductivity spectroscopy) comparison. Special influence of structural disorder diffusion.