Nanotubes form sensitive sensors
1 min read
Researchers in the University of Warwick’s Department of Chemistry have found a way of producing carbon nanotubes such that they instantly form a highly sensitive ready made electric circuit.
According to the team – Ioana Dumitrescu (left), Professor Julie Macpherson (centre), Professor Patrick Unwin (right) and Neil Wilson – they used chemical vapour deposition and lithography to create disk shaped ultra microelectrodes from single walled carbon nanotubes. The nanotubes are deposited on the surface in a random, but relatively even, manner. Because they overlap sufficiently, they create a single complete metallic microcircuit across the disk. The nanotubes are also said to take up less than 1% of the disk’s surface area.
This latter property is said to cope with low signal to noise ratios and helps to screen out background noise. Claiming an increase in sensitivity of 1000 times over conventional ultramicroelecrode sensors, the researchers also say response times improve by a factor of ten.
The Warwick research team is already exploring how these devices can be used to measure levels of neurotransmitters, but it also believes the ultra microelectrodes have potential application in fuel cell catalysis.
Until now, researchers were aware that carbon nanotubes appeared to be useful in this area, but were uncertain whether it was due to the properties of the carbon nanotubes per se or impurities in their production.
The Warwick researchers have proven that it is the properties of the carbon nanotubes themselves that are useful for catalysis.
