Piezoelectric Thin Films of ZnO Nanorods/Nanowalls Grown by Chemical Bath Deposition
This study presents a comparison of the piezoelectric properties of nanostructured thin films made of arrays of vertically oriented ZnO nanorods (ZnO NRs) over ITO glass substrate and of ZnO nanowalls (ZnO NWs) over aluminium substrate. Both nanostructures were synthesized on a large area through chemical bath deposition. The morphological, structural, and chemical characteristics of the produced nanostructures were investigated in order to assess the crystal quality and purity. To this purpose, we used different techniques, such as field emission scanning electron microscopy, atomic force microscopy, energy dispersive x ray analysis, powder x ray diffraction, x ray photoelectron spectroscopy, and photoluminescence spectroscopy. Moreover, the piezoelectric response of the nanostructured films was assessed through piezoresponse force microscopy. This technique was employed to obtain a quantitative evaluation of the piezoelectric coefficient <inline formula><tex math notation="LaTeX"{d_{33}/tex math>/inline formula> of the film. We obtained <inline formula><tex math notation="LaTeX"{d_{33}/tex math>/inline formula> values as high as (7.01 0.33) pm/V for ZnO NRs and (2.63 0.49) pm/V for ZnO NWs films.
IEEE Transactions on Nanotechnology