MANHASSET, N.Y. — Tiny nanotube brushes with bristles more than thousand times finer than a human hair have been created by researchers of Rensselaer Polytechnic Institute and the University of Hawaii.
The University of Hawaii scientists, working at Manoa in Honolulu, included Prof. Mehrdad Ghasemi-Nejhad, Dr. Anyuan Cao, and Vinod Veedu. The team from RPI (Troy, N.Y.) was led by Dr. Pulickel Ajayan, a world-renown expert in nanotechnology located at the Henry Burlage Professor of Materials Science and Engineering.
These brushes can be used to sweep up nanodust, as electronic micro-switches, to paint micro capillaries, and even clean up pollutants in water. The bristles' incorporate carbon nanotubes measuring just 30 nm across that are flexible enough to yield when pushed from the side.
The scientists grow bristles from hot, carbon-laden gas on to threads of silicon carbide finer than baby's hair. The researchers show how the brushes can sweep up piles of nanodust. They have also shown that the brushes can be used to paint microstructures, by dipping them into a solution of iron oxide with the minute brush hairs picking up the red oxide particles that can then be wiped on to a bare surface.
Conventional brush bristles, made of animal hairs, synthetic polymer fibers, and metal wires, are prone to break down at the nanoscale. To work at the nano-scale, researchers realized that a different kind of material was needed. The small size, strength, elasticity, and ability to conduct electricity make carbon nanotubes ideal bristle material, the scientists reported.