Synthesis of ultra long thread like ZnO nanowires with enhanced growth rate by low cost limited volume heating method

Abstract

In this work, long thread like ZnOnanowireswith faster growth rate is synthesized on silicon substrate by limited volume heating system in presence of ammonium hydroxide (NH4OH) solution. Hydrothermal synthesis of ZnOnanowireswere carried out using zinc nitrate and hexamethylenete-tramine(HMTA) precursors for different process duration. The morphological and structural study of ZnOnanowireswere investigated by scanning electron microscopy (SEM), x-ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM) techniques. EDS mapping was used to investigate the elemental analysis of the material. ZnOnanowireswith long thread like morphology spread throughout the substrate have been observed. The average length of the ZnO nanowiresis found to be around 21 μm with a growth rate of 2.8 μm/hour for a growth period of 7.5 hours. XRD pattern of ZnOnanowiresclearly reveal that the ZnO nanowires are primarily grown along the c-axis direction. TEM images further conrm the formation of ZnO nanowires and HRTEM image depicts that nanowires have good crystalline properties. EDS mapping shows the uniform distribution Zn and O element throughout the nanowire