Influence of the synthesis parameters on hydrothermally grown ZnO nanowires dedicated to mechanical energy harvesting

International audienceWe demonstrate that vertical well-aligned crystalline ZnO nanowires (NWs) arrays were grown on ZnO/Au/Ti/Si substrates by a hydrothermal method. Different thicknesses of ZnO seed layers were prepared by radio-frequency sputtering followed by a post-annealing treatment in air at 400°C. The effects of deposition time and annealing treatment of ZnO seed layers on the subsequent growth of ZnO NWs were investigated using X-ray diffraction (XRD) and scanning electron microscopy (SEM). In this work it was found that the morphology of ZnO NWs strongly depends on both the thickness and the heat treatment of the ZnO seed layers. The improved control of the morphology of ZnO nanowire arrays may lead to an enhanced performance of the resulting piezoelectric energy harvesting devices based on ZnO