2006 APS March Meeting
Monday–Friday, March 13–17, 2006;
Baltimore, MD
Session B4: Advances in ZnO Materials Physics and Applications
11:15 AM–2:15 PM,
Monday, March 13, 2006
Baltimore Convention Center
Room: 308
Sponsoring
Units:
DMP FIAP
Chair: Tom Myers, West Virginia University
Abstract ID: BAPS.2006.MAR.B4.4
Abstract: B4.00004 : Growth, Assembly, and Characterization of ZnO Nanostructures on Ag Films*
1:03 PM–1:39 PM
Preview Abstract
Abstract
Author:
Julia W. P. Hsu
(Sandia National Laboratories)
In the past decade, significant advances have been made in the synthesis of
ZnO nanostructures. The next step in making these nanomaterials useful is to
assemble them on surfaces in a controlled and desired fashion. In this talk,
I will discuss the growth of complex ZnO nanostructures via a solution
method in which organic templates are used to control assembly of these
nanostructures on substrate surfaces. The low temperature aqueous growth
method used in this work is an environmentally benign process, which is
compatible with organic templates and modifiers, can be used to grow large
areas uniformly, and has potential for inexpensive manufacturing. To control
the assembly of these solution grown nanostructures, we modify the substrate
surfaces with patterned self-assembled monolayers, which in turn determines
the final spatial organization of the ZnO nanorods. This is a bottom-up
approach in which materials are deposited only where they are needed. Using
this approach, we have achieved excellent control in spatial placement,
selectivity, crystal orientation, and nucleation density. In addition,
complex, hierarchical structures have been synthesized by controlling
solution chemistry and growth conditions. Due to lack of inversion symmetry
in hexagonal crystal, ZnO is a piezoelectric material with Zn (0001) polar
and O (000$\bar {1})$ polar surfaces exhibiting drastically different
physical and chemical properties. Hence, it is important to determine the
orientation of the ZnO nanorods on surfaces. Using piezoelectric force
microscopy (PFM) and a well-characterized ZnO single crystal reference, we
have measured the amplitude and phase of piezoelectric responses of over 100
individual ZnO rods. The phase of the PFM signal is 180\r{ } from the
applied electric field, indicating that the nanorods are [0001] oriented.
This result contradicts what would have been expected based on an
examination of rod morphology. Also, the PFM amplitude of the nanorods was
found to be significantly larger than that of the ZnO single crystal. The
origin behind this observation and the variation among different nanorods
will be discussed.
*In collaboration with D. Scrymgeour, Z. R. Tian, N. C. Simmons, C. M. Matzke, J. A. Voigt, and J. Liu
To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2006.MAR.B4.4