The enhanced performance of piezoelectric nanogenerator by increasing zinc precursor concentration during the growth of ZnO nanorods on stainless steel foil

This study aims to investigate the structural and morphology of ZnO nanorods in the variation of precursor ratio on stainless steel substrate and its piezoelectric nanogenerator performance. ZnO nanorods are grown on a stainless steel substrate that has been coated with ZnO as a seed layer by a modified hydrothermal method in the variation of molar ration between Zinc nitrate tetrahydrate (ZNT) and hexamethylenetetramine (HMT). X-ray diffraction (XRD) and scanning electron microscope (SEM) were performed for structural properties and morphology characterization. The performance of the piezoelectric nanogenerator was carried out by measuring voltage and current in applying an external force to the device. The ZnO-nanorods has a hexagonal wurtzite structure. The average length of ZnO-nanorods increased and the average diameter decreased by increasing ZNT/HMT ratio. The current and voltage of the piezoelectric nanogenerator increased with increasing by increasing the zinc nitrate ratio. These results indicate that the ZNT and HMT precursor ratio is playing an important role in the growth of ZnO nanorods that implicates the performance of the piezoelectric nanogenerator with stainless steel substrate.