Lab talk
May 21, 2009
Oak Ridge team builds 3D nanofence
A unique, three-dimensional (3D), biaxially textured, oxide nanofence comprised of single crystal MgO nanobelt segments or links was synthesized via epitaxial growth on (100) SrTiO3 substrates. Individual, single-crystal MgO nanobelt segments comprising the nanofence have a square cross-section with dimensions in the range of 10–20 nm and with lengths from 100 nm to 1 µm. X-ray diffraction shows that the 3D MgO nanofence has an epitaxial relation with (100) SrTiO3 substrates with a cube-on-cube, {100}<100> orientation and with full-width-half-maximum values of (200) ω-scan and (110) ψ-scan with 4.5o and 5.5o, respectively. Such a biaxially textured oxide nanofence with single-crystal segments can be used as a 3D nanotemplated substrate for the epitaxial growth of wide-ranging, 3D, electronic, magnetic and electromagnetic nanodevices.
The synthesis of oxide nanobelts in a reproducible and organized manner has been a goal of researchers in the field of nanotechnology for almost a decade. Ever since the seminal paper published by Z L Wang's group on the first report of ZnO nanobelts (which is now the most cited paper in nanomaterials), the potential for oxide nanobelt-based devices has captured the imagination of the community. However, there have been no reports of controlled synthesis of nanobelts in an organized manner.
The current work demonstrates that this is not only possible for a 1D array of nanobelts, but that three interpenetrating arrays of 1D nanobelts resulting in a 3D nanofence comprised of nanobelt segments is possible. The simple method used to fabricate this heteroepitaxial nanofence structure can potentially be extended to a range of other oxide materials. The nanofence structure was synthesized using a modified VLS growth technique via pulsed laser ablation.
The team reported its work in Nanotechnology.
About the author
The work was performed at the Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee, US. Dr Sung Hun Wee is a research assistant professor at the Department of Materials Science and Engineering, University of Tennessee and works closely with Dr Amit Goyal at ORNL. Dr Karren More and Dr Eliot Specht are Distinguished Staff Members at ORNL. Dr Amit Goyal is a ORNL/UT-Battelle Corporate Fellow and a Battelle Distinguished Inventor.
