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Silver nanowire networks have demonstrated significant potential as semi-transparent electrodes for various applications. However, for their widespread utilisation in devices, upscaled coating technologies such as screen-printing need to be explored and related to this, the formulation of suitable inks is indispensable. This work contributes to this effort by the synthesis of Ag-NW based formulations. The rheological characteristics that are essential for screen-printing are obtained by the addition of hydrophobically modified cellulose. The electrical and optical characteristics of screen-printed features on PET are compared by a Van der Pauw method and UV-vis spectroscopy. Despite the presence of the cellulose additive, the screen-printed electrodes exhibit a transmittance from 92.8% to 57.3% and a sheet resistance down to 27 Ohm sq -1 . Based on the percolation theory in composites, a mathematical expression is presented, which allows the in-depth analysis of the resulting opto-electrical properties. The application potential of the nanowire-containing formulations is finally demonstrated by screen-printing functional, flexible electroluminescent devices.

Integration of electronic circuit components onto flexible materials such as plastic foils, paper and textiles is a key challenge for the development of future smart applications. Therefore, conductive metal features need to be deposited on temperature sensitive substrates in a fast and straightforward way. The feasibility of these emerging (nano-) electronic technologies depends on the availability of well-designed deposition techniques and on novel functional metal inks. As ultrasonic spray coating (USSC) is one of the most promising techniques to meet the above requirements, innovative metal organic decomposition (MOD) inks are designed to deposit silver features on plastic foils. Various amine ligands were screened and their influence on the ink stability and the characteristics of the resulting metal depositions were evaluated to determine the optimal formulation. Eventually, silver layers with excellent performance in terms of conductivity (15% bulk silver conductivity), stability, morphology and adhesion could be obtained, while operating in a very low temperature window of 70 °C-120 °C. Moreover, the optimal deposition conditions were determined via an in-depth analysis of the ultrasonically sprayed silver layers. Applying these tailored MOD inks, the USSC technique enabled smooth, semi-transparent silver layers with a tunable thickness on large areas without time-consuming additional sintering steps after deposition. Therefore, this novel combination of nanoparticle-free Ag-inks and the USSC process holds promise for high throughput deposition of highly conductive silver features on heat sensitive substrates and even 3D objects.

Few-layer graphene (FLG) was catalytically formed on vertically aligned diamond nanorods (DNRs) by a high temperature annealing process. The presence of 4-5 layers of FLG on DNRs was confirmed by transmission electron microscopic studies. It enhances the field electron emission (FEE) behavior of the DNRs. The FLG-DNRs show excellent FEE characteristics with a low turn-on field of 4.21 V μm -1 and a large field enhancement factor of 3480. Moreover, using FLG-DNRs as cathode markedly enhances the plasma illumination behavior of a microplasma device, viz not only the plasma current density is increased, but also the robustness of the devices is improved.

The formation and properties of (110)-textured P-doped microcrystalline CVD diamond were studied. Based on several microscopy techniques, with a special emphasis on electron backscattered diffraction, a detailed determination of the grain orientations with respect to the exact [110] axis is given. The different orientations present in the film, in combination with low phosphine concentrations in the gas phase, lead to a variation in P incorporation that can vary over three orders of magnitude, as determined with cathodoluminescence mapping. The role of the surface morphology in the observation of these large incorporation differences is explained. Hall measurements confirm that the films are n-type conductive with a thermal activation energy of 0.56 eV. Based on B-doped substrates, pn junctions were created, showing a rectification ratio of nearly 10(4) at ± 25 V.

Solid-state nanopores of only a few nanometres in size show a great potential for applications such as molecule detection and DNA sequencing. In most cases, the fabrication of such a nanopore requires the high energy beam of a transmission electron microscope (TEM) or focused ion beam (FIB) tool to drill or reshape a small hole in a freestanding membrane. Here, we present a novel method to reduce the size of existing nanopores using electron-beam-induced deposition (EBID) of carbon in a conventional scanning electron microscope (SEM). The existing nanopores are etched in a silicon membrane using anisotropic wet etching and can be shrunk down to a few nanometres using EBID. This paper discusses the parameters that influence the rate of shrinking and provides an insight into the underlying mechanism.

Nanoimprint lithography is used to directly pattern the conjugated polymer semiconductor poly(3-hexylthiophene) (P3HT). We obtain trenches with aspect ratios up to 2 and feature sizes as small as 50 nm in this polymer. The application to organic solar cells is shown by creating an interpenetrated donor-acceptor interface, based on P3HT and N,N'-ditridecyl-3,4,9,10-perylenetetracarboxylic diimide (PTCDI-C(13)), deposited from the vapor phase to reduce shadow effects. A planarizing layer of spin-coated zinc oxide (ZnO) nanoparticles is used to reduce the roughness of the layer stack. The response of the photovoltaic devices follows the increased interface area, up to a 2.5-fold enhancement.