Complexity of Electron Transport in Nanoscale Molecular Junctions

In this dissertation, we analyse the charge transport of nanoscale molecular junctions in mechanically controllable break junction (MCBJ) experiments. In particular, we focus on the characterization of molecular features going beyond the "single-peak" picture, that is, considering features in the measurements in addition to themost prominent one...

A Novel Multiple-Ring Aromatic Spacer Based 2D Ruddlesden–Popper CsPbI₃ Solar Cell with Record Efficiency Beyond 16%

Two-dimensional (2D) Ruddlesden–Popper (RP) CsPbI₃ perovskite possesses superior phase stability by introducing steric hindrance. However, due to the quantum and dielectric confinement effect, 2D structures usually exhibit large exciton binding energy, and the charge tunneling barrier across the organic interlayer is difficult to...

Long-Range Charge Transport via Redox Ligands in Quantum Dot Assemblies

We present a strategy to actively engineer long-range charge transport in colloidal quantum dot assemblies by using ligand functionalities that introduce electronic states and provide a path for carrier transfer. This is a shift away from the use of inactive spacers to modulate charge transport through the lowering of the tunneling barrier...

Monte Carlo simulation of the secondary electron yield of silicon rich silicon nitride

The effect of doping in Si3N4 membranes on the secondary electron yield is investigated using Monte Carlo simulations of the electron-matter interactions. The effect of the concentration and the distribution of the doping in silicon rich silicon nitride membranes is studied by using the energy loss function as obtained from ab initio density...

Atomic Layer Deposition of ZnO on InP Quantum Dot Films for Charge Separation, Stabilization, and Solar Cell Formation

To improve the stability and carrier mobility of quantum dot (QD) optoelectronic devices, encapsulation or pore infilling processes are advantageous. Atomic layer deposition (ALD) is an ideal technique to infill and overcoat QD films, as it provides excellent control over film growth at the sub-nanometer scale and results in conformal...

Various aspects of quantum transport through single molecules: Amechanical break-junction study

This dissertation concerns transport measurements in single-molecule junctions using the mechanically controlled break junction (MCBJ) technique. It describes various aspects that play a role in charge transport through single molecules, in order to develop the necessary knowledge to ultimately develop electronic devices based on intrinsic...

Electrical characterization of nanoparticle and protein networks

This thesis describes the research directed towards practical realization of an on-chip biosensing technology and that of understanding charge transport mechanisms in organic and biological nanoobjects. For this, silicon-based chips with metallic nanoelectrodes were fabricated using electron-beam lithography and metal evaporation. The final...

Molecular Electronics: When Multiple Orbitals Matter

Relating the 3D electrode morphology to Li-ion battery performance; a case for LiFePO₄

One of the main goals in lithium ion battery electrode design is to increase the power density. This requires insight in the relation between the complex heterogeneous microstructure existing of active material, conductive additive and electrolyte providing the required electronic and Li-ion transport. FIB-SEM is used to determine the three...

OPE3: A model system for single-molecule transport

In this dissertation, charge-transport through individual organic molecules is investigated. The single molecules are contacted with two-terminal mechanically controllable break junction gold electrodes and their electrical and mechanical behavior studied at room and low temperature.

Charge Transport Through Single-Molecule Junctions: Experiments and Theory

In the pursuit of down-sizing electronic components, the ultimate limit is the use of single molecules as functional devices. Molecules can also provide additional functionalities compared to semiconductors. Using synthetic chemistry, an almost endless choice of molecular structures and compositions is available. With the proper knowledge, one...

Charge Carriers and Excited States in Supramolecular Materials

The field of organic electronics has been thriving for the last decades due to growing commercial interest. One of the advantages of using organic materials as semiconductors is the possibility to tune their optoelectronic properties by modifying the chemical structure and organization of the building blocks. In this thesis, the properties of...

Charge Transport in Disordered Molecular Systems

How does classical reality emerge from quantum mechanics? When does an electron in a molecule stop behaving as a wave and start behaving as a particle? What is the best way to describe the intermediate regime? Can quantum mechanical effects be put to practical use in molecular electronics? These are the questions that this thesis asks and...

Self-assembly and semiconductivity of an oligothiophene supergelator

A bis(trialkoxybenzamide)-functionalized quaterthiophene derivative was synthesized and its self-assembly properties in solution were studied. In non-polar solvents such as cyclohexane, this quaterthiophene ?-system formed fibril aggregates with an H-type molecular arrangement due to synergistic effect of hydrogen bonding and ?-stacking. The...

Charge transport along molecular wires

Imagine plastic electronics ... Consumer products such as mobile phones, mp3 players and palmtop computers that do not break when you accidentally drop them, with flexible displays. Moreover, these all plastic products would be cheaper than the current products based on conventional semi conductors. Apart from these advantaged, there is also a...

Charge transport in disordered organic field-effect transistors

In this thesis we study charge transport in organic semiconductors. We do this by focusing on the physical characterization of disordered organic field-effect transistors. It will be made clear that the disorder in the polymer films is crucial for the interpretation of the data. The field-effect transistor geometry allows variation of the charge...

Charge transport phenomena in thin-film cathodes

Spontaneous resistance switching and low-frequency noise in quantum point contacts