Synthesis, electrical characterization, and gas sensing properties of molybdenum oxide nanorods

Abstract

Gas sensors have been prepared by using single crystalline MoO3 nanorods. Structures 50–150nm and up to 15μm in length were synthesized by template directed hydrothermal synthesis. Gas sensing tests showed responses to NO2 up to 740% and to NH3 up to 570%. Moreover, preliminary electrical characterizations were performed, as a function of temperature in 20–520°C range temperature, by means of current-voltage measurements. I-V dependence studies show a linear increase in current at low voltage and a quadratic increase at higher voltages. A study of the current-temperature dependence shows that at high temperature current is thermally active and successively decreases that can be explained by taking in account a change of material morphology.