Blowing bubbles could provide a surprising solution to the problem of separating and aligning tangled nanowires and nanotubes, and pave a new way of producing nanoscale electronic components, such as transistors, a new study by American researchers has revealed.
As part of their research, Guihua Yu and Charles Lieber of Harvard University, and Anyuan Cao of the University of Hawaii, US, used nitrogen gas to blow bubbles of an epoxy polymer containing silicon nanowires and caught the resulting film on a surface.
Then they examined the resulting film under both optical and electron microscopes, and found that the nanowires and nanotubes had become neatly lined up vertically towards the top of the bubble and evenly spread out across the surface.
Varying the concentration of tubes or wires in the mixture altered the density of nanomaterials, but not their alignment, the researchers found.
The team believes stress generated on the surface of the bubble, as it expands, pulls the tubes and wires into line, although they are not sure of it.
Having a simple way to align nanowires and nanotubes with a particular density could help integrate such components into electronic and optical devices, the researchers said.
The findings appear in the journal Nature Nanotechnology, reports New Scientist.