A5063148289- Organic Electronics and Photovoltaics
- Molecular Junctions and Nanostructures
- Force Microscopy Techniques and Applications
- X-ray Diffraction in Crystallography
- Conducting polymers and applications
- Crystallization and Solubility Studies
- Surface Chemistry and Catalysis
- Thin-Film Transistor Technologies
- Organic Light-Emitting Diodes Research
- Surface and Thin Film Phenomena
- Quantum Dots Synthesis And Properties
- Crystallography and molecular interactions
- Liquid Crystal Research Advancements
- Advanced Chemical Physics Studies
- Chalcogenide Semiconductor Thin Films
- Semiconductor materials and devices
- Machine Learning in Materials Science
- Electron and X-Ray Spectroscopy Techniques
- Perovskite Materials and Applications
- Rare-earth and actinide compounds
- Analytical Chemistry and Sensors
- Synthesis and properties of polymers
- Block Copolymer Self-Assembly
- nanoparticles nucleation surface interactions
- Semiconductor materials and interfaces
Graz University of Technology
2016-2025
SOLID (Austria)
1999-2023
Nawi Graz
2019-2022
Medical University of Graz
2022
Institute of Crystallography
2022
Institute of Solid State Physics
2008-2020
Université Libre de Bruxelles
2013-2019
Elettra-Sincrotrone Trieste S.C.p.A.
2019
BioTechMed-Graz
2016-2017
University of Graz
1998-2013
An increase or modification of structural order in the vicinity a solid substrate is known for wide range materials. For molecular materials crystallizing on surface it has been observed that new polymorphic forms may exist near interface with substrate, which have structures different to those bulk. Such phases are termed as substrate‐induced (SIPs). The presence an SIP compound class can be crucial significance terms their physical properties. However, factors drive such process not...
Abstract Entanglement of states is one the most surprising and counter-intuitive consequences quantum mechanics, with potent applications in cryptography computing. In organic materials, particularly significant manifestation spin-entangled triplet-pair state, which mediates spin-conserving fission spin-0 singlet exciton into two spin-1 triplet excitons. Despite long theoretical experimental exploration, nature state inter-triplet interactions have proved elusive. Here we use a range...
Integrating metal–organic frameworks (MOFs) into microfabrication processes will benefit from controlled vapor-phase deposition techniques. This study presents a molecular layer method that enables area-selective and oriented growth of zeolitic imidazolate framework-8 (ZIF-8) films. Substrates functionalized with self-assembled monolayers (SAMs) different end groups (alkyl, phenyl, hydroxyl, carboxyl, amine, imidazole) allow tuning the degree crystallographic orientation in resulting MOF...
Here, we present a hot injection synthesis of colloidal Ag chalcogenide nanocrystals (Ag(2)Se, Ag(2)Te, and Ag(2)S) that resulted in exceptionally small nanocrystal sizes the range between 2 4 nm. exhibit band gap energies within near-infrared spectral region, making these materials promising as environmentally benign alternatives to established infrared active containing toxic metals such Hg, Cd, Pb. We Ag(2)Se detail, giving size-tunable luminescence with quantum yields above 1.7%. The...
Combined experimental and theoretical investigations on thin films of pentacene are performed in order to determine the structure film phase. Grazing incidence x-ray diffraction is used for studying a with nominal thickness $180\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$. The crystal found exhibit lattice parameters $a=0.592\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$, $b=0.754\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$, $c=1.563\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$,...
Controlling the morphology of soluble small molecule organic semiconductors is crucial for application such materials in electronic devices. Using a simple dip-coating process we systematically vary film drying speed to produce range morphologies, including oriented needle-like crystals. Structural characterization as well electrical transistor measurements show that intermediate velocities most uniformly aligned films.
A new 2:1 donor (D):acceptor (A) mixed-stacked charge-transfer (CT) cocrystal comprising isometrically structured dicyanodistyrylbenzene-based D and molecules is designed synthesized. Uniform 2D-type morphology manifested by the exquisite interplay of intermolecular interactions. In addition to its appealing structural features, unique optoelectronic properties are unveiled. Exceptionally high photoluminescence quantum yield (ΦF ≈ 60%) realized non-negligible oscillator strength S1...
Activation energy for charge transport, carrier concentration and recombination rate are identified to strongly affect the device characteristics.
Abstract Based on the powerful concept of embedded dipole self‐assembled monolayers (SAMs), highly conductive interfacial layers are designed, which allow tuning contact resistance organic thin‐film transistors over three orders magnitude with minimum values well below 1 kΩ cm. This not only permits realization competitive p‐type (pentacene‐based) devices rigid as flexible substrates, but also enables n‐type (C 60 ‐based) comparable characteristics utilizing same electrode material (Au). As...
Materials against ice formation and accretion are highly desirable for different industrial applications daily activities affected by icing. Although several concepts have been proposed, no material has so far shown wide-ranging icephobic features, enabling durability manufacturing on large scales. Herein, we present gradient polymers made of 1,3,5,7-tetravinyl-1,3,5,7-tetramethylcyclotetrasiloxane (V
J-aggregation has been shown to be beneficial for light amplification in single crystals of π-conjugated organic molecules. In the case H-aggregation, criteria such processes are still under debate. It also that H-aggregate arrangements with considerable π–π overlap detrimental amplification. We show here a proper alignment molecules crystal lattice, which minimizes between adjacent molecules, gives rise (random) stimulated emission from cofacial similar herringbone aggregates.
The behavior of amorphous cellulose model thin films upon heat treatment is investigated. Upon treatment, a structural rearrangement in the from featureless to fibrillar structure observed which correlates with regeneration time and total content as proven by atomic force microscopy X-ray photoelectron spectroscopy. ATR-IR spectroscopy proves presence stronger hydrogen bonds treated surfaces originate reorganization chains pore structure. accompanied an increased surface hydrophobicity,...
The energy positions of frontier orbitals in organic electronic materials are often studied experimentally by (inverse) photoemission spectroscopy and theoretically within density functional theory. However, standard exchange-correlation functionals result too small fundamental gaps, may lead to wrong orbital ordering, do not capture polarization-induced gap renormalization. Here we examine these issues a strategy for overcoming them studying the gas phase bulk structure molecule...
GIDVis is a software package based on MATLAB specialized for, but not limited to, the visualization and analysis of grazing-incidence thin-film X-ray diffraction data obtained during sample rotation around surface normal. allows user to perform detector calibration, stitching, intensity corrections, standard evaluation (e.g. cuts integrations along specific reciprocal-space directions), crystal phase etc. To take full advantage measured in case rotation, pole figures can easily be calculated...
Vapour-phase deposition of copper dicarboxylate metal–organic framework thin films with an out-of-plane orientation and accessible porosity.
We report on the fabrication and characterization of parylene C thin layers for organic electronic devices passivation gate dielectric field effect transistors (OFETs) development. The investigated were deposited from vapour phase in thickness ranging 3 to 800 nm at room temperature. surface morphology characterized by ellipsometry AFM technique. quality structures analysed X-ray reflectivity diffraction as well micro-Raman spectroscopy. measurements confirmed perfect homogeneity structural...
Iron oxide-based exchange-coupled nanomagnets consisting of antiferromagnetic wüstite (FexO) cores covered by ferrimagnetic metal ferrite shells (see figure) are chemically synthesized in a simple one-pot procedure. The synthesis allows independent size, shape, and compositional control. strong exchange coupling at the core/shell interface results unique magnetic properties.
Three-in-one: A novel distyrylbenzene-based material forms J-type aggregates in single crystals with highly polarized and bright red emission, giving rise to optical gain narrowing, for which different mechanisms (amplified spontaneous laser emission stimulated resonance Raman scattering) are observed. These correlated the favorable intrinsic macroscopic properties of crystal, particular orientation molecules crystal surface. Detailed facts importance specialist readers published as...
A method for the preparation of uniaxially oriented thin films terthiophene (20–50 μm thick) is introduced. It relies on crystal growth with a Bridgman-type process that decouples nucleation and phenomena. An effective thermal gradient 6–11.6 °C/mm has been used in which sample (terthiophene powder deposited either glass or fluorinated substrates) displaced from hot zone to cold at constant rate 2.5–5 μm/s. The size orientation crystals have investigated by polarized optical microscopy X-ray...
The presence of surface-induced crystal structures is well known within organic thin films. However, the physical parameters responsible for their formation are still under debate. In present work, we polymorphic molecule dihexyl-terthiophene in films prepared by different methods using solution-based like spin-coating, dip-coating and drop-casting, but also vapour deposition. characterised various X-ray diffraction to investigate crystallographic properties microscopy techniques (atomic...