A5027510844- Molecular Junctions and Nanostructures
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Supramolecular Self-Assembly in Materials
- Protein Structure and Dynamics
- Electrochemical Analysis and Applications
- Advanced Memory and Neural Computing
- Conducting polymers and applications
- Alzheimer's disease research and treatments
- Graphene research and applications
- Polydiacetylene-based materials and applications
- Advanced biosensing and bioanalysis techniques
- Photoreceptor and optogenetics research
- Acoustic Wave Resonator Technologies
- Lipid Membrane Structure and Behavior
- Gold and Silver Nanoparticles Synthesis and Applications
- Enzyme Structure and Function
- Parkinson's Disease Mechanisms and Treatments
- Quantum and electron transport phenomena
- Advanced Sensor and Energy Harvesting Materials
- Crystallography and molecular interactions
- RNA and protein synthesis mechanisms
- Quantum Dots Synthesis And Properties
- Dendrimers and Hyperbranched Polymers
- Biofuel production and bioconversion
University of Limerick
2016-2025
Science Foundation Ireland
2021-2024
University College Cork
2006-2014
National University of Singapore
2013
Tyndall National Institute
2007-2012
Queen's University Belfast
2011
École Polytechnique
2006-2009
Centre National de la Recherche Scientifique
2006-2009
International Energy Research Centre
2009
Northern Arizona University
1996-1997
A challenge in molecular electronics is to control the strength of molecule-electrode coupling optimize device performance. Here we show that non-covalent contacts between active component (in this case, ferrocenyl a ferrocenyl-alkanethiol self-assembled monolayer (SAM)) and electrodes allow for robust with minimal energy broadening level, precisely what required maximize rectification ratio diode. In contrast, strong chemisorbed through result large broadening, leakage currents poor By...
Abstract Research on the piezoelectric response of biomolecules has intensified following demonstration open circuit voltages over 20 V in biopiezoelectric generators. Organic nanotubes, fibers, and micro-islands have been grown studied; however, lack fundamental understanding effect nature hinders rational design biomaterials to provide a tailor-made response. Advances high performance computing facilitated use quantum mechanical calculations predict full tensor biomolecular crystals,...
Abstract Realization of a self-assembled, nontoxic and eco-friendly piezoelectric device with high-performance, sensitivity reliability is highly desirable to complement conventional inorganic polymer based materials. Hierarchically organized natural materials such as collagen have long been posited exhibit electromechanical properties that could potentially be amplified via molecular engineering produce technologically relevant piezoelectricity. Here, by using simple, minimalistic, building...
It was proposed in 1974 that molecules could rectify, but molecular diodes with simultaneously high rectification ratios, yields of working junctions, and reproducibility are rare, despite a huge body experimental work. Although every type junction contains certain distribution defects induced by the topography surface, roles these device performance rarely studied. We show control over bottom electrode self-assembled monolayer (SAM)-based junctions terms number grains, width grain...
Peptide assemblies are ideal components for eco-friendly optoelectronic energy harvesting devices due to their intrinsic biocompatibility, ease of fabrication, and flexible functionalization. However, date, practical applications have been limited the difficulty in obtaining stable, high-performance devices. Here, it is shown that tryptophan-based simplest peptide cyclo-glycine-tryptophan (cyclo-GW) forms mechanically robust (elastic modulus up 24.0 GPa) thermally stable 370 °C monoclinic...
To visualize amyloid β (Aβ) aggregates requires an uncontaminated and artifact-free interface. This paper demonstrates the interface between graphene pure water (verified to be atomically clean using tunneling microscopy) as ideal platform for resolving size, shape, morphology (measured by atomic force of Aβ-40 Aβ-42 peptide assemblies from 0.5 150 hours at a 5-hour time interval with single-particle resolution. After confirming faster aggregation in comparison Aβ-40, stable set oligomers...
Diphenylalanine (FF) represents the simplest peptide building block that self-assembles into ordered nanostructures with interesting physical properties. Among self-assembled structures, FF nanotubes display notable stiffness and piezoelectric parameters (Young's modulus = 19–27 GPa, strain coefficient d33 18 pC/N). Yet, inorganic alternatives remain major materials of choice for many applications due to higher piezoelectricity. Here, aiming broaden motif in chemistry, we designed three...
Single crystal L-amino acids can exhibit technologically useful piezoelectric and nonlinear optical properties. Here we predict, using density functional theory, the charge strain voltage tensors of racemic amino acid DL alanine, use modeling data to guide first macroscopic nanoscopic measurements on DL-alanine single crystals polycrystalline aggregates. We demonstrate generation up 0.8 V from films under simple manual compression, twice as high other crystals. Our results suggest that net...
Molecular stacking modes, generally classified as H-, J-, and X-aggregation, play a key role in determining the optoelectronic properties of organic crystals. However, control transformation specific molecule is an unmet challenge,
The apparent piezoelectricity of biological materials is not yet fully understood at the molecular level. In particular, dynamic noncovalent interactions, such as host–guest binding, are included in classical piezoelectric model, which limits rational design eco-friendly supramolecular materials. Here, inspired by conformation-dependent mechanoresponse Piezo channel proteins, we show that guest–host interactions can amplify electromechanical response a conformationally mobile peptide...
Abstract The physical characteristics of supramolecular assemblies composed small building blocks are dictated by molecular packing patterns in the solid‐state. Yet, structure–property correlation is still not fully understood. Herein, we report unexpected cofacial to herringbone stacking transformation a aromatic bipyridine through co‐assembly with acetylated glutamic acid. unique solid‐state structural results enhanced properties organizations. methodology was further expanded obtain...
Variation in the molecular architecture significantly affects electronic and supramolecular structure of biomolecular assemblies, leading to dramatically altered piezoelectric response. However, relationship between building block chemistry, crystal packing quantitative electromechanical response is still not fully understood. Herein, we systematically explored possibility amplify piezoelectricity amino acid-based assemblies by engineering. We show that a simple change side-chain acetylated...
ConspectusThis Account describes a body of research in atomic level design, synthesis, physicochemical characterization, and macroscopic electrical testing molecular devices made from ferrocene-functionalized alkanethiol molecules, which are diodes, with the aim to identify, resolve, failure modes that cause leakage currents. The mismatch size between ferrocene headgroup alkane rod makes waxlike highly dynamic self-assembled monolayers (SAMs) on coinage metals show remarkable atomic-scale...
We studied the electrochemical behavior of self-assembled monolayers (SAMs) n-alkanethiolates with ferrocenyl (Fc) termini on gold (S(CH2)nFc, n = 0–15) in relation to their supramolecular structures (characterized by photoemission spectroscopy (PES) supported molecular dynamics (MD) simulations) elucidate origin nonideal features commonly observed cyclic voltammograms (CVs) these SAMs systematically changing from 0 15. For all CV data are dominated a main peak for Fc units directly contact...
We investigated the origin of odd–even effects in molecular diodes based on self-assembled monolayers (SAMs) ferrocenyl-terminated n-alkanethiolates S(CH2)nFc with n = 6–15 Ag or Au surfaces contacted EGaIn top electrodes. These SAMs have different M–S–C bond angles 180° when M and 104° causing a multitude performance diodes. By changing using several characterization techniques, we were able to systematically identify rationalize electronic structure device. Changing from 6 15 resulted an...