A5023079440- Molecular Junctions and Nanostructures
- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Advanced Thermoelectric Materials and Devices
- Graphene research and applications
- Surface Chemistry and Catalysis
- Surface and Thin Film Phenomena
- Porphyrin and Phthalocyanine Chemistry
- Magnetic and transport properties of perovskites and related materials
- Carbon Nanotubes in Composites
- Machine Learning in Materials Science
- Advanced Chemical Physics Studies
- Electronic and Structural Properties of Oxides
- Heusler alloys: electronic and magnetic properties
- Quantum and electron transport phenomena
- Ferroelectric and Piezoelectric Materials
- Organic and Molecular Conductors Research
- Advanced Electron Microscopy Techniques and Applications
- Hydrogen Storage and Materials
- Fiber-reinforced polymer composites
- Semiconductor materials and devices
- Perovskite Materials and Applications
- 2D Materials and Applications
- Force Microscopy Techniques and Applications
- Microwave Dielectric Ceramics Synthesis
University of Bath
2015-2018
Chalmers University of Technology
2012-2014
University College Cork
2010-2013
Tyndall National Institute
2010-2012
Technical University of Denmark
2009
National Academy of Sciences of Ukraine
2004
Bioinspired structures are promising as improved catalysts for various redox reactions. One example is metal hangman-porphyrines (MHP), which recently have been suggested oxygen reduction/evolution reaction (ORR/OER). The unique properties of the MHPs attributed to both hangman scaffold and C6F5 side groups. Herein, OER/ORR over transition investigated by density functional theory calculations within an electrochemical framework. A comparison landscape MHP, porphyrine (MP)...
A combination of normal-incidence x-ray standing-wave (NIXSW) spectroscopy, photoelectron spectroscopy (XPS), scanning tunneling microscopy (STM), and density-functional theory (DFT) has been used to investigate the interaction a number phthalocyanine molecules (specifically, SnPc, PbPc, CoPc) with Ag(111) surface. The metal-surface distances predicted by DFT calculations for SnPc/Ag(111) $(2.48\text{ }\text{\AA{}})$ CoPc/Ag(111) $(2.88\text{ are in good agreement our NIXSW experimental...
A first-principles account of the observed limiting thickness oxide films formed on aluminum during oxidizing conditions is presented. The results uncover enhanced bonding oxygen to thin alumina in contact with metallic that stems from charge transfer between a reconstructed oxide-metal interface and adsorbed molecules. are compared traditional Cabrera-Mott (CM) model, which classical continuum model. Within CM charged surface species metal ions generate (Mott) potential drives oxidation. An...
We present a computational screening study of ternary metal borohydrides for reversible hydrogen storage based on density functional theory. investigate the stability and decomposition alloys containing 1 alkali atom, Li, Na, or K (M(1)); alkali, alkaline earth 3d/4d transition atom (M(2)) plus two to five (BH(4))(-) groups, i.e., M(1)M(2)(BH(4))(2-5), using number model structures with trigonal, tetrahedral, octahedral, free coordination borohydride complexes. Of over 700 investigated...
Experimental and modelling investigation of Sr/Mo (co-)doped CaMnO<sub>3</sub> highlighted the role Mn<sup>3+</sup> presence domain boundaries in thermal transport thermoelectric properties.
Conformational changes caused by adsorption can dramatically affect a molecule's properties. Despite extensive study, however, the exact mechanisms underpinning conformational switching are often unclear. Here we show that conformation of prototypical flexible molecule, free-base tetra(4-bromophenyl) porphyrin, adsorbed on Cu(111), depends critically its precise site and that, remarkably, large dominated van der Waals interactions between molecule substrate surface. A combination scanning...
We have applied density functional theory and high-resolution transmission electron microscopy to investigate the relationship between chemically induced strain charge transfer on structural, electronic, vibrational, thermoelectric properties of misfit layered cobaltites (M2CoO3)0.6CoO2 (M = Mg, Ca, Sr, Ba). The phonon states are analyzed rationalized by accounting for effects internal transfer, lay foundations disentangle these a promising oxide material. found that choice different...
In this article we study in detail the interaction of cobalt phthalocyanine (CoPc) with Ag(111) surface by means density functional theory calculations (DFT). We discuss electronic and geometric differences adsorbed CoPc as it interacts different binding sites surface, yielding deeper insight into adsorption mechanism organometallic molecules noble metal surfaces. interpret experimentally observed 4-fold to 2-fold symmetry reduction upon surfaces caused effects originating from nonsymmetric...
Abstract Scanning probe-actuated single molecule manipulation has proven to be an exceptionally powerful tool for the systematic atomic-scale interrogation of molecular adsorbates. To date, however, extent which conformation affects force required push or pull a not been explored. Here we probe mechanochemical response two tetra(4-bromophenyl)porphyrin conformers using non-contact atomic microscopy where find large difference between lateral forces manipulation. Remarkably, despite sharing...
The prediction of the lattice constant binary body centered cubic crystals is performed in terms first principle calculations and machine learning. In particular, 1541 are calculated using density functional theory. Results from calculations, corresponding information periodic table, mathematically tailored data stored as a dataset. Data mining reveals seven descriptors which key to determining where contribution also discussed visualized. Support vector regression (SVR) technique...
Shuttlecock shaped metal-phthalocyanine (MPc) can adsorb on a substrate surface having the central metal atom either down or up and possibility of reversible switching between these two adsorption configurations shows great promise for use in nanomechanical devices. Using density functional theory we investigate mechanism internal conformational inversion germanium, tin lead phthalocyanine terms geometry, energy barrier reaction, redox properties atom. We have found same GePc SnPc but...
The reversible switch between two electronically and/or geometrically distinct states of a single molecule adsorbed on well-characterized substrate is high technological interest due to its possible use as devices and novel molecular memories. We have studied shuttlecock-shaped metal phthalocyanines, which can adsorb surfaces in adsorption configurations, depending if the central atom points toward or away from surface, we report tin-phthalocyanine (SnPc) an Ag(111) surface using density...
[Bi0.87SrO2]2[CoO2]1.82 (BSCO) is one of the best p-type thermoelectric oxides but its structural and electronic properties are still poorly understood. BSCO a misfit-layered compound consisting an incommensurate stacking hexagonal CoO2 double rock-salt BiSrO2 layers. Here we combine experimental computational approaches to investigate crystallographic structure as well transport properties. Considering different approximations for subsystems stacking, present model that agrees with both...
We investigated the structure of tungsten bronze barium neodymium titanates Ba6–3nNd8+2nTi18O54, which are exploited as microwave dielectric ceramics. They form a complex nanostructure, resembles nanofilm with stacking layers ∼12 Å thickness. The synthesized samples Ba6–3nNd8+2nTi18O54 (n = 0, 0.3, 0.4, 0.5) characterized by pentagonal and tetragonal columns, where A cations distributed in three symmetrically inequivalent sites. Synchrotron X-ray diffraction electron energy loss spectroscopy...
Semiconducting Ba6−3x Nd8+2x Ti18O54 ceramics (with x = 0.00 to 0.85) were synthesized by the mixed oxide route followed annealing in a reducing atmosphere; their high-temperature thermoelectric properties have been investigated. In conjunction with experimental observations, atomistic simulations performed investigate anisotropic behavior of lattice thermal conductivity. The show promising n-type relatively high Seebeck coefficient, moderate electrical conductivity, and temperature-stable,...
Square atomic configurations of two-dimensional gold and platinum are designed on the basis density functional theory calculations. Calculations reveal that Au9 Pt9 clusters form energetically stable perfect square structures. Combining alternating two allows for formation infinite sheets Au9, Pt9, Au18Pt18. The electronic state reveals Au18Pt18 retain metallic characteristics whereas also possess magnetic properties. In addition, multilayered up to five layers four layers, respectively,...
Hybrid materials composed of different functional structural units offer the possibility tuning both thermal and electronic properties a material independently. Using quantum mechanical calculations, we investigate change in thermoelectric transport graphene hydrogen-terminated carbon nanoribbons (CNRs) when these are placed on SrTiO3 (001) surface (STO). We predict that p-type n-type composite can be achieved by coupling graphene/CNR to terminations STO. show CNR significantly altered...
A combination of experimental and computational techniques has been employed to explore the crystal structure thermoelectric properties A-site-deficient perovskite La1/3NbO3 ceramics. Crystallographic data from X-ray electron diffraction confirmed that room temperature is orthorhombic with Cmmm as a space group. Atomically resolved imaging analysis showed there are two distinct sites: one occupied La vacancies, second site fully unoccupied. The diffuse superstructure reflections observed...