Electrical transport properties of single ZnO nanorods

TLDR: In this article, single ZnO nanorods with diameters of ∼130nm were grown on Au-coated Al2O3 substrates by catalyst-driven molecular beam epitaxy.

Abstract: Single ZnO nanorods with diameters of ∼130nm were grown on Au-coated Al2O3 substrates by catalyst-driven molecular beam epitaxy. Individual nanorods were removed from the substrate and placed between Ohmic contact pads and the current–voltage characteristics measured as a function of temperature and gas ambient. In the temperature range from 25to150°C, the resistivity of nanorods treated in H2 at 400°C prior to measurement showed an activation energy of 0.089±0.02eV and was insensitive to the ambient used (C2H4,N2O,O2 or 10% H2 in N2). By sharp contrast, the conductivity of nanorods not treated in H2 was sensitive to trace concentrations of gases in the measurement ambient even at room temperature, demonstrating their potential as gas sensors.