ORCID Profile
0000-0003-3435-4600
Current Organisation
University of Twente
Does something not look right? The information on this page has been harvested from data sources that may not be up to date. We continue to work with information providers to improve coverage and quality. To report an issue, use the Feedback Form.
In Research Link Australia (RLA), "Research Topics" refer to ANZSRC FOR and SEO codes. These topics are either sourced from ANZSRC FOR and SEO codes listed in researchers' related grants or generated by a large language model (LLM) based on their publications.
Organometallic Chemistry | Other Chemical Sciences | Transition Metal Chemistry
Expanding Knowledge in the Chemical Sciences | Expanding Knowledge in the Physical Sciences |
Publisher: American Chemical Society (ACS)
Date: 24-01-2017
DOI: 10.1021/ACS.LANGMUIR.6B03721
Abstract: We study the degradation process of closely spaced silver and gold nanocubes under high-energy electron beam irradiation using transmission electron microscopy (TEM). The high aspect ratio gaps between silver and gold nanocubes degraded in many cases as a result of protrusion and filament formation during electron beam irradiation. We demonstrate that the molecular coating of the nanoparticles can act as a protective barrier to minimize electron-beam-induced damage on passivated gold and silver nanoparticles.
Publisher: Royal Society of Chemistry (RSC)
Date: 2021
DOI: 10.1039/D0SC04555A
Abstract: Herein, we report the first room temperature switchable Fe( iii ) molecular spin crossover (SCO) tunnel junction.
Publisher: Royal Society of Chemistry (RSC)
Date: 2019
DOI: 10.1039/C9NA00107G
Abstract: Understanding the influence of structural properties on the electronic structure will pave the way for optimization of charge transport properties of SAM devices.
Publisher: Royal Society of Chemistry (RSC)
Date: 2021
DOI: 10.1039/D0TC05773H
Abstract: This work gives new insights in the conduction mechanisms across biomolecular junctions and demonstrates that proteins can reversibly change between in- and coherent tunnelling pathways defined by the protein cage and the amount of co-factor.
Publisher: American Chemical Society (ACS)
Date: 17-08-2021
Publisher: American Chemical Society (ACS)
Date: 26-11-2021
DOI: 10.1021/JACS.1C09549
Publisher: American Chemical Society (ACS)
Date: 05-12-2018
DOI: 10.1021/JACS.8B09086
Abstract: This paper reports highly efficient coherent tunneling in single-molecule wires of oligo-ferrocenes with one to three Fc units. The Fc units were directly coupled to the electrodes, i.e., without chemical anchoring groups between the Fc units and the terminal electrodes. We found that a single Fc unit readily interacts with the metal electrodes of an STM break junction (STM = scanning tunneling microscope) and that the zero-voltage bias conductance of an in idual Fc molecular junction increased 5-fold, up to 80% of the conductance quantum G
Publisher: Wiley
Date: 30-11-2022
Abstract: Recently it is discovered that molecular junctions can be pushed into the Marcus Inverted region of charge transport, but it is unclear which factors are important. This paper shows that the mechanism of charge transport across molecular wires can be switched between the normal and Marcus Inverted regions by fine‐tuning the molecule–electrode coupling strength and the tunneling distance across oligophenylene ethynylene (OPE) wire terminated with ferrocene (Fc) abbreviated as S‐OPE n Fc ( n = 1–3). Coherent tunneling dominates the mechanism of charge transport in junctions with short molecules ( n = 1), but for n = 2 or 3 redox reactions become important. By weakening the molecule—electrode interaction by interrupted conjugation, S‐CH 2 ‐OPE n Fc, intramolecular orbital gating can occur pushing the junctions completely into the Marcus Inverted region. These results indicated that weak molecule—electrode coupling is important to push junctions into the Marcus Inverted Region.
Publisher: Springer Science and Business Media LLC
Date: 06-2020
Publisher: Wiley
Date: 14-09-2022
Abstract: In biomolecular electronics, the role of structural order in charge transport (CT) is poorly understood. It has been reported that the metal oxide cores of protein cages (e.g., iron oxide and ferrihydrite nanoparticles (NPs) present in ferritin and E2-LFtn, which is E2 protein engineered with an iron-binding sequence) play an important role in the mechanism of CT. At the same time, the NP core also plays a major role in the structural integrity of the proteins. This paper describes the role of structural order in CT across tunnel junctions by comparing three iron-storing proteins. They are (1) DNA binding protein from starved cells (Dps, diameter (∅) = 9 nm) (2) engineered archaeal ferritin (AfFtn-AA, ∅ = 12 nm) and (3) engineered E2 of pyruvate dehydrogenase enzyme complex (E2-LFtn, ∅ = 25 nm). Both holo-Dps and apo-Dps proteins undergo CT by coherent tunneling because their globular architecture and relative structural stability provide a coherent conduction pathway. In contrast, apo-AfFtn-AA forms a disordered structure across which charges have to tunnel incoherently, but holo-AfFtn-AA retains its globular structure and supports coherent tunneling. The large E2-LFtn always forms disordered structures across which charges incoherently tunnel regardless of the presence of the NP core. These findings highlight the importance of structural order in the mechanism of CT across biomolecular tunnel junctions.
Publisher: Springer Science and Business Media LLC
Date: 21-11-2022
DOI: 10.1038/S41563-022-01402-2
Abstract: To realize molecular-scale electrical operations beyond the von Neumann bottleneck, new types of multifunctional switches are needed that mimic self-learning or neuromorphic computing by dynamically toggling between multiple operations that depend on their past. Here, we report a molecule that switches from high to low conductance states with massive negative memristive behaviour that depends on the drive speed and number of past switching events, with all the measurements fully modelled using atomistic and analytical models. This dynamic molecular switch emulates synaptic behavior and Pavlovian learning, all within a 2.4-nm-thick layer that is three orders of magnitude thinner than a neuronal synapse. The dynamic molecular switch provides all the fundamental logic gates necessary for deep learning because of its time-domain and voltage-dependent plasticity. The synapse-mimicking multifunctional dynamic molecular switch represents an adaptable molecular-scale hardware operable in solid-state devices, and opens a pathway to simplify dynamic complex electrical operations encoded within a single ultracompact component.
Publisher: Research Square Platform LLC
Date: 20-01-2022
DOI: 10.21203/RS.3.RS-1156230/V1
Abstract: To realise molecular scale electrical operations beyond the von Neumann bottleneck, new types of multi-functional switches are needed that mimic self-learning or neuromorphic computing by dynamically toggling between multiple operations that depend on their past. Here we report a molecule that switches from high to low conductance states with massive negative memristive behaviour that depends on the drive speed and number of past switching events, with all measurements fully modelled using atomistic and analytical models. This dynamic molecular switch (DMS) emulates synaptic behaviour and Pavlovian learning, all within a 2.4 nm thick layer that is three orders of magnitude thinner than a neuronal synapse. The DMS provides all fundamental logic gates necessary for deep learning because of its time-domain and voltage-dependent plasticity. The synapse-mimicking multi-functional DMS represents adaptable molecular scale hardware operable in solid-state devices opening a pathway to simplify dynamic complex electrical operations encoded within a single ultra-compact component.
Publisher: Wiley
Date: 19-06-2021
Abstract: This paper describes the transition from the normal to inverted Marcus region in solid‐state tunnel junctions consisting of self‐assembled monolayers of benzotetrathiafulvalene (BTTF), and how this transition determines the performance of a molecular diode. Temperature‐dependent normalized differential conductance analyses indicate the participation of the HOMO (highest occupied molecular orbital) at large negative bias, which follows typical thermally activated hopping behavior associated with the normal Marcus regime. In contrast, hopping involving the HOMO dominates the mechanism of charge transport at positive bias, yet it is nearly activationless indicating the junction operates in the inverted Marcus region. Thus, within the same junction it is possible to switch between Marcus and inverted Marcus regimes by changing the bias polarity. Consequently, the current only decreases with decreasing temperature at negative bias when hopping is “frozen out,” but not at positive bias resulting in a 30‐fold increase in the molecular rectification efficiency. These results indicate that the charge transport in the inverted Marcus region is readily accessible in junctions with redox molecules in the weak coupling regime and control over different hopping regimes can be used to improve junction performance.
Start Date: 05-2020
End Date: 12-2024
Amount: $440,000.00
Funder: Australian Research Council
View Funded Activity