The growth of ZnO nanorods based on hydrothermal and measurement of conductivity

Zinc Oxide (ZnO) nanorods have been attracted interests as a gas molecule-catcher material in gas sensor applications. In this research, ZnO nanorods was grown on the surface of interdigitated electrode arrays substrate by using a hydrothermal method. The hydrothermal process consists of two steps, i.e., the seeding process and the growth of ZnO nanorods. The precursor material used in seeding process was Zinc Acetate Dihydrate (Zn(CH3COO)2.2H2O), while Zinc Nitrate Tetrahydrate (Zn(NO3)2.6H2O) was used as a precursor in the growth of ZnO nanorods. The sample was characterized by using scanning electron microscopy (SEM) and I-V Curve testing to determine the conductivity properties. SEM results show that ZnO nanorods has an average diameter of <100 nm. The result from the I-V curve with applied voltage in the range of 1–30 volt shows that the greater value of the applied voltage produces a decrease of the resistance value. The resistance value obtained at a given voltage of 1 volt is 7.8 kohm, while at a voltage of 30 volts is 0.5 kohm. The I-V curve profile indicates that interface between ZnO nanorods and Au-electrode shows a Schottky barrier characteristics. The gas effect with various parameters of CO gas concentrations, applied voltages and temperatures is under study.