Quasi 1-D metal oxide single crystal chemiresistors are about to occupy their specific niche in the real world solid
state sensorics. The major expected advantage of this kind of sensors with respect to available granular thin film sensors
will be their smaller size and stable, reproducible and calculable performance within a wide range of operating
conditions. To be able to compete in sensitivity with the best available nanocrystalline thin film sensors, one has to use
very fine nanowires with the effective diameter of the order of ten nanometers. Fabrication of nanostructures
reproducibly and controllably in this size domain remains a challenging task. The second challenge is a control of the
selectivity of these nanosensors. In this report, a few exemplary approaches to grow and functionalize the prospective
nanosensors are presented. Namely, in order to produce the nanostructures with the reduced diameter of the conducting
channel, we grow nanowires with the oscillating morphologies where mesoscopic, several microns long segments are
connected by the segments with much smaller diameters. In order to tune the sensitivity and selectivity of these sensors
the influence of the surface sensitization with catalyst particles of Ni/NiO and Pd were examined.
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