Analysis of Electrical and Impedance Properties of the Group-I (Li, Na, K & Cs) Doped ZnO Nanorods

ZnO and ZnO seed layers doped with group-I elements (Li, Na, K & Cs) were prepared by spin coating. Seed layer is used to prepare nanorods by hydrothermal method. Doped and undoped nanorods structural, surface morphology, and electrical conductivity properties are characterized by x-ray diffraction, field emission scanning electron microscopy (FESEM), and impedance spectroscopy. Undoped and doped ZnO nanorods show wurtzite structure without a secondary phase. Vertically aligned hexagonal-shaped nanorods are observed from FESEM and surface porosity is calculated. A single conduction process with a Debye relaxation peak is obtained in all the nanorods from impedance analysis. Electrical conductivity $$({\sigma }_{ac})$$ measurement of undoped and doped ZnO nanorods follows Janscher’s power law with high-frequency exponent values which leads to quantum mechanical tunneling conduction. Doped ZnO nanorods show a higher $${\sigma }_{ac}$$ values than ZnO. A reduction of potential barrier height and activation energy is observed in the ZnO nanorods doped with group-I elements.