Parisa Fakhri - Instrumentation Research Group, Niroo Research Institute (NRI), Tehran, Iran.
Mohammad Kashfi - Mechanical Engineering Department, Ayatollah Boroujerdi University, Boroujerd, Iran
Babak Amini - Instrumentation Research Group, Niroo Research Institute (NRI), Tehran, Iran
Neda Yavari - Instrumentation Research Group, Niroo Research Institute (NRI), Tehran, Iran.
Roohollah Bagherzadeh - Institute for Advanced Textile Materials and Technologies, Textile Engineering Department, Amirkabir University of Technology, Tehran, Iran

Zinc Oxid nanorods (ZnO NRs) have been widely investigated due to their unique properties and remarkable performance in electronics, optics, and photonics. In this paper, ZnO NRs were grown by hydrothermal method at different conditions. The scanning electron microscope (SEM) and X-ray diffraction (XRD) were used to characterize the morphology and structure of ZnO NRs. Three different process conditions were investigated and characterized. Finally, vertically aligned ZnO NRs with hexagonal structure were grown of PTFE substrate. The XRD results also confirmed the orientation of ZnO NRs along the c-axis direction perpendicular to the substrate through presence of the dominant peak related to the (002) diffraction plane. The nanogenerator device based on ZnO NRs was then prepared and its piezoelectric performance was evaluated under periodic impacts at low frequency. Such piezoelectric nanogenerator working at low frequencies are expected to have various applications in wearable and self-powered devices to convert mechanical energy from the human motions to usable electrical energy

Piezoelectric, Nanogenerator, ZnO Nanorods, Hydrothermal Method