Metal complexes and 2D materials like graphene were combined to produce structures that can function as sensors. Using spin crossover materials, both in bulk single crystal form and in thin layer... Show moreMetal complexes and 2D materials like graphene were combined to produce structures that can function as sensors. Using spin crossover materials, both in bulk single crystal form and in thin layer form, graphene-based electronic sensors were produced and characterized that can detect spin switches in the spin crossover materials. At the same time, the light-activatable ruthenium complexes were researched for their application in sensors that can monitor reactions that were triggered by light. We found that the photoreaction of a ruthenium complex with a nucleobase could be triggered in paper-based graphene devices. Moreover, we found that this ruthenium scaffold could also be used to increase the signal strength in a nanopore-based DNA detection system. Lastly, a ruthenium complex was designed that had a sensing function built in, as a dual-function molecule with a sensing and anticancer function. Overall, combining metal complexes with graphene was found to be a successful strategy to produce hybrid structures for sensing. Show less
Graphene nanoribbons (GNRs) are used as a current carrying substrate in investigation of current-induced forces in a low-temperature STM (chapter 2). We demonstrate induced migration of Co adatoms... Show moreGraphene nanoribbons (GNRs) are used as a current carrying substrate in investigation of current-induced forces in a low-temperature STM (chapter 2). We demonstrate induced migration of Co adatoms on GNRs and on Au(111) using voltage pulses from the STM tip and we argue that motion is due to thermal excitations rather than the wind force. In chapter 3 we show that voltage signal is induced in a graphene strip when a droplet of ionic liquid is moved across its surface. Here we show that even deionized water can induce voltage over charged graphene surface due to the polarizability of water molecules. In chapter 4 we present a method for fabrication of graphene nanoelectrodes which we further test electrically in a modified STM. For the first time we demonstrate that the gap between two graphene nanoelectrodes can be tuned with subnanometric precision Show less
In this work, we illustrate unconventional approaches towards the fabrication of edge functionalized graphene nanostructures and bidimensional architectures in polymeric and metallic supports, with... Show moreIn this work, we illustrate unconventional approaches towards the fabrication of edge functionalized graphene nanostructures and bidimensional architectures in polymeric and metallic supports, with an outlook towards molecular sensing devices. Particularly, starting from the most established knowledge on the chemistry of graphene, we selectively functionalize the edges of graphene either via electrochemistry, plasma chemistry and solution chemistry. In fact, the chemistry at the edges, particularly at the nanoscale, tailors the properties of graphene without perturbing the honeycomb lattice of carbon atoms, thus without compromising the intrinsic nature of graphene. Via unconventional tools such as microtomy and molecular break junctions, we finally realize chemically designed platforms such as transistors, nanogaps and nanoribbons to be further integrated into sensing devices, such as zero-depth nanopore. Remarkably, we demonstrate the possibility of achieving extremely precise graphene nanostructures while going beyond the highly complicated demands of conventional top-down fabrications. At the same time, we specifically address the chemistry at the edges of graphene moving beyond synthetic approaches. Selectively edge functionalized graphene becomes available also on large area films and tailored graphene nanostructures, looking for the integration of graphene in the next generation sensing devices. Show less
