Photonic crystals in biology

Poster Session, Tuesday, June 15
Theme A1 - B702
Synthesis of ZnO Nanowires and Nanorods
Sadullah Öztürk 1 , 1 , 1, Zafer Ziya Öztürk 1 *
1 Gebze Institute of Technology, Science Faculty, Department of Physics, Kocaeli 41400, Turkey
Abstract-In this study, fabrication of ZnO nanostructures such as nanowires and nanorods will be explained in details. ZnO nanowires were
grown by cathodically induced sol-gel deposition using an anodic aluminum oxide (AAO) template which is approximately 70 nm diameter and
10 μm length. So vertically aligned ZnO nanowires were grown in AAO template by applying cathodic voltage in aqueous Zinc Nitrate solution
at 23 ºC. For electrochemical deposition, three-electrode system was used. The ZnO nanowires are approximately 65 nm diameter and 10 μm
lengths. For fabrication of ZnO nanorods hydrothermal technique was used. Firstly sol-gel ZnO solution was coated on glass substrate by spin
coating for seed layer. Then ZnO nanorods were grown in Zinc nitrate and HMTA aqueous solution at 90 ºC about 3h. The ZnO nanorods are
approximately 40 nm diameter. The vertical nanowires and nanorods were characterized by scanning electron microscope (SEM).
ZnO nanostructures are attractive material in last decade
because of their n-type semiconducting behavior with large
exciton binding energy (60 meV) and a large band gap (3.37
eV). ZnO nanostructures can be used in novel devices, such as
photonic devices and very sensitive chemical sensors etc. In
literature, there are many techniques for fabricating of ZnO
nanowires such as electrochemical and chemical vapor
deposition, and also for fabrication ZnO nanorods such as
hydrothermal, sonochemical and chemical vapor deposition
technique [1,2]. In this study, ZnO nanowires were grown in
an AAO template with 75 nm diameter and m in length by
electrochemical deposition techniques. The AAO template
was grown on Al foil with two anodization techniques and the
details were given [1]. ZnO nanowires were electrodeposited
in this template with applying -1.5V at room temperature
about 2h. Then AAO template was etched in NaOH aqueous
solution. So ZnO nanowires was obtained with 70 nm
ZnO nanowires was shown in
figure 1.
On the other hand for preparing ZnO nanorods, ZnO seed
layer solution was deposited on glass with spin coating at
2500 rpm about 30s. Then the coated glass was dried in an
oven at 130°C for 5min. and this step was repeated 5 times.
Finally, ZnO seed layer glass was annealed 300 °C
approximately 1h. The ZnO nanorods were grown in
Zn(NO 3 ) 2 .6H 2 O and HMTA equmolar aqueous solution at
90 °C about 3h on ZnO seed layer coated glass. For preparing
of nanorods, cleavable laboratory bottle was used. ZnO seed
layer coated glass was put in vertically. ZnO nanorods were
40nm diameter and 800nm length. ZnO nanorods were shown
in Figure 2
It is clearly seen from figure1 that, ZnO nanowires were
deposited in AAO template. Because the aspect ratio was very
high so the nanowires were come together.
Figure 2. Top view of ZnO nanorods
It is clearly seen fron fig. 2 that ZnO nanorods were
completely covered surface of the ZnO seed layer coated
glass.
In summary, in this study, two different types of ZnO
nanostructures were synthesized by using different techniques.
If these two techniques were compared, a hydrothermal
technique was easier. In our future works, these nanostructures
will be used as gas sensor such as NO2, CO, H2 and volatile
organic compound.
*Corresponding author: zozturk@gyte.edu.tr
[1] N. Tüüzer, Z. Z. Öztürk, 95, 781-
787, 2009
[2] S. Öüzer, Z.Z. Öztürk,
Fabrication of ZnO nanowires at room temperature by cathodically
induced sol–gel method in press, DOI: 10.1007/s00339-009-5504-8
[3] Z.L. Wang, J. Phys: Cond. Matt. 16, R829 (2004).
[4] L. Schmidt-Mende, J. MacManus-Driscoll, Materials Today, 10,
40 (2007).
Figure 1. Top view of the free standing of ZnO nanowire
6th Nanoscience and Nanotechnology Conference, zmir, 2010 403