Synthesis Of Well-aligned ZnO Nanocone Arrays And Its Optical Properties

Well-aligned ZnO nanocone arrays (NCAs) were prepared on fluorine doped tin oxide(FTO) substrates using highly ordered ZnO nanorod arrays (NRAs) as templates to guide thegrowth via a hydrothermal method. It was found that the highly ordered ZnO NRAspre-formed on FTO played a critical role in dictating the further growth of the well-alignedZnO NCAs from them. Only disordered ZnO nanocones on FTO were obtained in the absenceof the highly ordered ZnO nanorod templates. The well-aligned ZnO nanocone arrays werecharacterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), UV–visibleabsorption, and photoluminescence (PL) spectroscopies. Experiments show that thewell-aligned ZnO nanocone arrays compose of ZnO and exhibit highly c-axis orientation,well crystalline and the average length of nanocone is as high as9μm. In addition, the UV-absorption spectroscopy indicated that the absorption of well-aligned ZnO nanocone arrayswas highest and the transmission of them was lowest due to its strong light-trapping effect,which may find important applications in, e.g., photovoltaics.In addition, the disordered ZnO nanocones, well-aligend ZnO nanocone arrays andordered ZnO nanorods were synthesis by hydrothermal growth. The optical properties of themwere compared by UV-visible absorption. It deduced that the ZnO nanocones have stronglight-trapping effect which makes them exhibit the lowest transmission. And thelight-trapping effect of well-aligned ZnO nanocone arrays is higer than disorded ZnOnanocones, indicative of the advantage of well-aligned ZnO nanocone arrays.