Nucleant layer effect on nanocolumnar ZnO films grown by electrodeposition

Different ZnO nanostructured films were electrochemically grown, using an aqueous solution based on ZnCl2, on three types of transparent conductive oxides grow on commercial ITO (In2O3:Sn)-covered glass substrates: (1) ZnO prepared by spin coating, (2) ZnO prepared by direct current magnetron sputtering, and (3) commercial ITO-covered glass substrates. Although thin, these primary oxide layers play an important role on the properties of the nanostructured films grown on top of them. Additionally, these primary oxide layers prevent direct hole combination when used in optoelectronic devices. Structural and optical characterizations were carried out by scanning electron microscopy, atomic force microscopy, and optical transmission spectroscopy. We show that the properties of the ZnO nanostructured films depend strongly on the type of primary oxide-covered substrate used. Previous studies on different electrodeposition methods for nucleation and growth are considered in the final discussion. We thank Prof. A. Segura of the Universitat de Valencia for the facilities with the sputtering equipment. This work was supported by the project PROMETEO/2009/074 from the Generalitat Valenciana. Reyes Tolosa, MD.; Damonte, LC.; Brine, H.; Bolink, HJ.; Hernández Fenollosa, MDLÁ. (2013). Nucleant layer effect on nanocolumnar ZnO films grown by electrodeposition. Nanoscale Research Letters. 8:135-144. https://doi.org/10.1186/1556-276X-8-135 Franklin JB, Zou B, Petrov P, McComb DW, Ryanand MP, McLachlan MA,J: Optimised pulsed laser deposition of ZnO thin films on transparent conducting substrates. Mater Chem 2011, 21: 8178–8182. 10.1039/c1jm10658a Jaroslav B, Andrej V, Marie N, Šuttab P, Miroslav M, František U: Cryogenic pulsed laser deposition of ZnO. Vacuum 2012, 86(6):684–688. 10.1016/j.vacuum.2011.07.033 Jae Bin L, Hyeong Joon K, Soo Gil K, Cheol Seong H, Seong-Hyeon H, Young Hwa S, Neung Hun L: Deposition of ZnO thin films by magnetron sputtering for a film bulk acoustic resonator. Thin Solid Films 2003, 435: 179–185. 10.1016/S0040-6090(03)00347-X Xionga DP, Tanga XG, Zhaoa WR, Liua QX, Wanga YH, Zhoub SL: Deposition of ZnO and MgZnO films by magnetron sputtering. Vacuum 2013, 89: 254–256. Reyes Tolosa MD, Orozco-Messana J, Lima ANC, Camaratta R, Pascual M, Hernandez-Fenollosa MA: Electrochemical deposition mechanism for ZnO nanorods: diffusion coefficient and growth models. J Electrochem Soc 2011, 158(11):E107-E110. Ming F, Ji Z: Mechanism of the electrodeposition of