Synthesis of aligned zinc oxide nanorods for humidity sensing

Aligned zinc oxide nanorods thin film was synthesized by the hydrothermal method. The nanorods were vertically aligned on an indium tin oxide substrate. The length of the nanorods can be controlled by repetitive reactions. Preliminary results of the humidity sensing properties of the nanorods are reported. A 450 nm thick nanorods thin film was measured in this paper. The resistance response under changing Relative Humidity (RH) is characterized. In contrast to most of related reports of humidity sensing by ZnO, a resistance increase of the nanorods during was observed when they are exposed to water molecules.