Hydrothermal zinc oxide nanowire growth using zinc acetate dihydrate salt
- PDF / 470,568 Bytes
- 7 Pages / 584.957 x 782.986 pts Page_size
- 55 Downloads / 255 Views
Yunus Eren Kalay Department of Metallurgical and Materials Engineering, Middle East Technical University, Ankara, Turkey
Husnu Emrah Unalana) Department of Micro and Nanotechnology, Middle East Technical University, Ankara, Turkey; and Department of Metallurgical and Materials Engineering, Middle East Technical University, Ankara, Turkey (Received 24 November 2011; accepted 13 March 2012)
Hydrothermal approach is widely used for the synthesis of zinc oxide (ZnO) nanowires. Zinc nitrate hexahydrate, zinc acetate and zinc chloride are three common salts that are used for synthesis. Among these, zinc nitrate hexahydrate is primarily used in many studies and zinc chloride is preferred for electrodeposition. In this work, zinc acetate dihydrate salt is used for the growth of ZnO nanowires and the effects of time, temperature, solution concentration and concentration ratios of the precursor chemicals are investigated. It is found that the growth time and solution concentration control the lengths of the nanowires, whereas the precursor concentration ratio and solution concentration control their diameter. High solution concentrations and high zinc acetate dihydrate concentrations lead to the development of thin film morphology. Optimum growth parameters are obtained and suggested for the use of zinc acetate dihydrate as a zinc source for growing ZnO nanowires with high aspect ratio (AR). The use of zinc acetate dihydrate leads to the formation of ZnO nanowires without impurities and eliminates the need for using extra capping agents.
I. INTRODUCTION
Electronic devices utilizing nanowires and nanorods are subject of great interest since they promise to have novel properties and be a substitute for devices made of conventional semiconducting thin film or bulk materials. ZnO, with its wide direct band gap (3.37 eV) and large exciton binding energy (60 meV), is a promising material for various applications. Nanostructures offer grainboundary and mostly defect-free single crystalline nature over their bulk counterparts, which could be beneficial for electronic and optoelectronic applications. Therefore, ZnO nanorods and nanowires have been a subject of intense study in recent years for their implementation in ultraviolet (UV) lasers,1 field emission devices,2,3 sensors,4,5 transistors,6 solar cells,7–9 piezo-nanogenerators,10,11 light emitting diodes.12 Several methods have been utilized for the synthesis of ZnO nanowires. Vapor phase transport,13,14 metal-organic chemical vapor deposition (MOCVD),15,16 and low temperature approaches17–34 are among a few of these methods. Low temperature growth methods for ZnO nanostructures include but not limited to sol-gel method,35,36 chemical bath deposition37 and hydrothermal a)
Address all correspondence to this author. e-mail: [email protected] DOI: 10.1557/jmr.2012.92 J. Mater. Res., Vol. 27, No. 11, Jun 14, 2012
methods. Hydrothermal synthesis is a robust and economic method for the growth ZnO nanowires that can be carried out with simple equipment unlike the other methods mentio
Data Loading...
