Workgroup Nanosensors

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The activities in the field of "nanosensor technology" focus on chemical sensors that operate in the gas phase. These are characterized by large (inner) surfaces to allow maximum interaction with the chemical substances to be detected. This large surface area is realized by using nanoscopic or nanoporous materials as sensitive layers. This requires the fabrication of suitable nanoparticles and nanostructures. A large number of sensitive materials have already been developed and investigated at IESM, partly in collaboration with other TUBAF institutes, for use in the gas phase (e.g., for breath analysis in the medical field or process fluid and environment analysis for Industry 4.0 applications). These include self-assembling nanocomposites based on metal nanoparticles (NP) and various organic linkers, coordination polymers, metal-organic networks (MOFs), and graphene-based materials. These are miniaturizable, easy to vary in composition, and therefore promising for high-sensitivity sensors. Nanoporous metal oxides (as humidity sensors) are also the subject of investigation at the institute. These sensitive materials are deposited on transducers developed at IESM. Monocrystalline Si wafers, glass, polymers or even paper serve as substrates for interdigital electrodes, which allow resistive or capacitive signals to be read out. In order to develop a fundamental understanding of how the sensors work, a large number of sensory tests are carried out at IESM during interaction with the molecules to be detected.

In the area of high temperature sensors, IESM is developing monolithic potentiometric solid electrolyte sensors for use in the float glass industry for the detection of H2S either in the gas phase or the molten tin.

An additional topic for the "Nanosensorics" working group is coating technology, since all sensitive materials must either be applied to transducers for measurement or provided with metal electrodes in order to be read out. Surface morphology and composition play a decisive role for the wetting and adhesion properties of the sensitive layers.