Mar 29, 2011
Hydro-tweezers build nanodevices
The assembly and alignment of nanowires or nanotubes is essential for building up nanodevices. However, manipulating nanowires in a controllable manner is still very challenging. To address the problem, a simple hydrodynamic focusing method has been developed to position and align nanowire arrays or single nanowires at specific locations. The team refers to the technique as "hydro-tweezers".
Researchers at the University of Western Ontario, Canada, are developing a bottom-up strategy for building nanosystems. The approach uses three flows, one sample flow in the middle of two sheath flows, to hydrodynamically focus nanocomponents ready for assembly.
The sample flow is clamped laterally by the two sheath flows, which act as a pair of hydro-tweezers. By adjusting the flow ratio of the sheath flow to the sample flow, it is possible to focus the sample flow and shift this stream over the entire flow field. If the sample flow contains suspended nanowires then these nanowires will deposit onto the surface beneath the sample flow.
The hydro-tweezers can be used to deliver nanowires to desired positions on a substrate and the approach could enable new applications in nanoelectronics, biosensors and materials science, with no material limitation.
More details, including images of deposited silver nanowires, can be found in the journal Nanotechnology.
About the author
The study was conducted by Prof. Jun Yang's group and its collaborators at the University of Western Ontario, Canada. The first author, Dr Mei Liu, is now at the School of Mechatronics Engineering and Automation, Shanghai University, China.