Modification of the optical and structural properties of ZnO nanowires by low-energy Ar+ ion sputtering
1 Departamento de Ciencia de los Materiales e Ingeniería Metalúrgica y Q.I., Facultad de Ciencias, Apdo. 40, Puerto Real, Cádiz, 11510, Spain
2 GdS-Optronlab Group, Departamento Física Materia Condensada, Edificio I+D, Universidad de Valladolid, Paseo de Belén 1, Valladolid, 47011, Spain
3 Laboratorio de Crecimiento de Cristales, Departamento de Física de Materiales, Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco Madrid, 28049, Spain
Nanoscale Research Letters 2013, 8:162 doi:10.1186/1556-276X-8-162Published: 9 April 2013
The effects of low-energy (≤2 kV) Ar+ irradiation on the optical and structural properties of zinc oxide (ZnO) nanowires (NWs) grown by a simple and cost-effective low-temperature technique were investigated. Both photoluminescence spectra from ZnO NW-coated films and cathodoluminescence analysis of individual ZnO NWs demonstrated obvious evidences of ultraviolet/visible luminescent enhancement with respect to irradiation fluence. Annihilation of the thinner ZnO NWs after the ion bombardment was appreciated by means of high-resolution scanning electron microscopy and transmission electron microscopy (TEM), which results in an increasing NW mean diameter for increasing irradiation fluences. Corresponding structural analysis by TEM pointed out not only significant changes in the morphology but also in the microstructure of these NWs, revealing certain radiation-sensitive behavior. The possible mechanisms accounting for the decrease of the deep-level emissions in the NWs with the increasing irradiation fluences are discussed according to their structural modifications.