A5033045933- Molecular Junctions and Nanostructures
- Microstructure and mechanical properties
- Surface and Thin Film Phenomena
- Advanced Materials Characterization Techniques
- Organic Electronics and Photovoltaics
- Hydrogen embrittlement and corrosion behaviors in metals
- Machine Learning in Materials Science
- Advanced materials and composites
- nanoparticles nucleation surface interactions
- Microstructure and Mechanical Properties of Steels
- Metal and Thin Film Mechanics
- Fusion materials and technologies
- Ion-surface interactions and analysis
- Quantum Dots Synthesis And Properties
- Nuclear Materials and Properties
- Organic and Molecular Conductors Research
- Advanced Chemical Physics Studies
- Semiconductor materials and interfaces
- Conducting polymers and applications
- Surface Chemistry and Catalysis
- Inorganic Chemistry and Materials
- Graphene research and applications
- Intermetallics and Advanced Alloy Properties
- Magnetic Properties and Applications
- Corrosion Behavior and Inhibition
Montanuniversität Leoben
2010-2025
Materials Center Leoben (Austria)
2014-2023
Imperial College London
2023
University of Helsinki
2011
Erich Schmid Institute of Materials Science
2010
Graz University of Technology
2003-2010
Austrian Academy of Sciences
2010
Humboldt-Universität zu Berlin
2007-2010
Ruhr University Bochum
2010
Massachusetts Institute of Technology
2007-2009
Self-assembled monolayers (SAMs) of organic molecules generally modify the surface properties when covalently linked to substrates. In electronics, SAMs are used fine-tune work functions inorganic electrodes, thereby minimizing energy barriers for injection or extraction charge carriers into out an active layer; a detailed understanding interface energetics on atomistic scale is required design improved interfaces. field molecular SAM itself (or, in some cases, one few molecules) carries...
Despite exhibiting the highest melting point of all metals, technological use tungsten is hampered by its room-temperature brittleness. Alloying with Re significantly ductilizes material which has been assigned to modified properties 1/2(111) screw dislocation. Using density functional theory, we show that alloying induces a transition from symmetric an asymmetric core and reduction in Peierls stress. This combination alloy as number available slip planes increased critical stress needed...
The energetics at the interfaces between metal and monolayers of covalently bound organic molecules is studied theoretically. Despite under consideration displaying very different frontier orbital energies, highest occupied molecular levels are found to be pinned a constant energy offset with respect Fermi level. In contrast, properties strongly impact work function. These interfacial phenomena rationalized in terms charge fluctuations electrostatics atomic length scale as determined by...
Self-assembled monolayers (SAMs) of organic molecules provide an important tool to tune the work function electrodes in plastic electronics and significantly improve device performance. Also, energetic alignment frontier molecular orbitals SAM with Fermi energy a metal electrode dominates charge transport single-molecule devices. On basis first-principles calculations on SAMs π-conjugated noble metals, we detailed description mechanisms that give rise intrinsically link these interfacial...
Abstract The low emission band at 2.2–2.3 eV in polyfluorene‐based conjugated materials is studied by various spectroscopic methods on defined copolymers of 9–9′‐difarnesyl‐fluorene with 9‐fluorenone, which can be seen as a model compound for degraded polyfluorenes. Absorption, electroluminescence, and photoluminescence the film (temperature‐dependent) solution (room temperature) reveal optical properties this low‐energy emerging polyfluorene‐type polymers upon degradation. All experimental...
Interface energetics are of fundamental importance in organic and molecular electronics. By combining complementary experimental techniques first-principles calculations, we resolve the complex interplay among several interfacial phenomena that collectively determine electronic structure strong electron acceptor tetrafluoro-tetracyanoquinodimethane chemisorbed on copper. The combination adsorption-induced geometric distortion molecules, metal-to-molecule charge transfer, molecule-to-metal...
A thorough understanding of the adsorption molecules on metallic surfaces is a crucial prerequisite for development and improvement functionalized materials. prominent representative within class π-conjugated 3,4,9,10-perylene-tetracarboxylic acid dianhydride (PTCDA) which, adsorbed Ag(111), Au(111) or Cu(111) surfaces, shows characteristic trends work-function modification, alignment molecular levels with substrate Fermi energy binding distances. We carried out density functional theory...
In this study, we compute grain boundary (GB) properties for a large set of GBs in bcc transition metals with special focus on W, Mo and Fe using ab initio density functional theory (DFT) semi-empirical second nearest neighbour modified embedded atom method (2NN-MEAM) potentials. The GB include energies, surface excess volume work separation, which analyse then compare to experimental data. We find that the used 2NN-MEAM potentials can predict general trends properties, but do not always...
We study the interface of an organic monolayer with a metallic surface, i.e., PTCDA (3,4,9,10-perylene-tetracarboxylic-dianhydride) on Ag(110), by means angle-resolved photoemission spectroscopy (ARPES) and ab initio electronic structure calculations. present tomographic method that uses energy momentum dependence ARPES data to deconvolute spectra into individual orbital contributions beyond limits resolution. This provides orbital-by-orbital characterization large adsorbate systems without...
The segregation of transition metal elements to grain boundaries in steels plays a critical role determining their cohesion. Here, we investigate the segregation, co-segregation, and cohesion effects various metals (Co, Cr, Cu, Mn, Mo, Ni, Nb, Ti, V W) different boundary characters ferritic-iron (α-Fe) through systematic, brute-force style configurational analysis utilising density functional theory calculations. We demonstrate that differing change not only co-segregation behaviours, but...
Metal work-function modification with the help of organic acceptors is an efficient tool to significantly enhance performance modern state-of-the-art molecular electronic devices. Here, prototypical acceptor 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane, F4TCNQ, characterized on Ag(111), Au(111), and Cu(111) metal surfaces by means density-functional theory calculations. Particular attention paid charge-transfer processes at metal-organic interface; a subtle balance between charge...
Abstract Self‐assembled monolayers (SAMs) are fundamental building blocks of molecular electronics and find numerous applications in organic (opto)electronic devices. Their properties decisively determined by their response to electric fields, which either applied externally (e.g., when biasing devices) or originate from within the monolayer itself case it consists dipolar molecules (which used tune charge‐injection barriers). This is typically described dielectric constant monolayer. In...
We report high throughput density functional theory (DFT) calculations to simulate segregation of s- and p-elements in Mo W. First, the preference solutes for interstitial or substitutional positions bulk is evaluated then energies different sites at a grain boundary (GB) free surface (FS) are computed. show that several change their site from position upon GB. With GB FS, changes cohesion can be calculated enhancing identified. The results striking similarity both W Mo. In addition, we...
Fundamental understanding of H localization in steel is an important step towards theoretical descriptions hydrogen embrittlement mechanisms at the atomic level. In this paper, we investigate interaction between and defects ferromagnetic body-centered cubic (bcc) iron using density functional theory (DFT) calculations. Hydrogen trapping profiles bulk lattice, vacancies, dislocations grain boundaries (GBs) are calculated used to evaluate concentrations these as a function temperature. The...