Hydrothermal zinc oxide nanowire growth with different zinc salts
- PDF / 627,383 Bytes
- 7 Pages / 584.957 x 782.986 pts Page_size
- 95 Downloads / 292 Views
Aysegul Afal Department of Metallurgical and Materials Engineering, Middle East Technical University, Ankara 06800, Turkey
Husnu Emrah Unalana) Department of Micro and Nanotechnology, Middle East Technical University, Ankara 06800, Turkey; Department of Metallurgical and Materials Engineering, Middle East Technical University, Ankara 06800, Turkey; and Center for Solar Energy Research and Applications, Middle East Technical University, Ankara 06800, Turkey (Received 31 May 2012; accepted 29 June 2012)
The effect of the use of different zinc salts as zinc sources during hydrothermal growth of zinc oxide nanowires was systematically investigated. Change in the temperature, pH, and transmittance of the growth solutions prepared with three different zinc salts was monitored and used to provide a broad explanation to the effect of the salt. In addition to conventional heating process, microwave heating of the growth solutions was also performed, and differences in the ZnO nanowires synthesized through both heating methods were examined. It was found that ionization of zinc in growth solutions is influencing the formation of ZnO nanowires leading to growth with different aspect ratios, and zinc acetate dihydrate salt allows the synthesis of nanowires with the highest aspect ratio. I. INTRODUCTION
A remarkable effort has been made on developing electronic devices utilizing nanowires and nanorods since they promise to have novel properties and be a substitute for devices made of conventional and bulk semiconducting materials. With its wide and direct band gap (3.37 eV) and large exciton binding energy (60 meV), zinc oxide (ZnO) is a promising material for various applications. ZnO nanorods and nanowires have been a subject of intense studies 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.12–15 Several methods have been utilized for the synthesis of ZnO nanowires. Vapor phase transport,16,17 metal organic chemical vapor deposition,18,19 and hydrothermal synthesis20–33 are among these methods. Hydrothermal method has its distinctive advantages such as cost-effectiveness and straightforward implementation compared to other alternatives. Researchers use different zinc salts such as zinc nitrate hexahydrate, zinc chloride, and zinc acetate dihydrate for the synthesis of ZnO nanowires within hydrothermal method. They also use additives like capping agents21 or strong bases22 to synthesize ZnO nanowires with high aspect ratio. Zinc nitrate hexahydrate salt is commonly preferred for the growth of ZnO nanowires via hydrothermal route.23
a)
Address all correspondence to this author. e-mail: [email protected] DOI: 10.1557/jmr.2012.258 J. Mater. Res., Vol. 27, No. 18, Sep 28, 2012
http://journals.cambridge.org
Downloaded: 11 Dec 2014
Zinc chloride, on the other hand, is usually utilized for electrodeposition.20 Zinc acetate dihydrate, although extensively used for seeding the nanowire grow
Data Loading...
