Miniature Carbon Monoxide Detector Based on Nanotechnology

A highly sensitive miniature carbon monoxide (CO) gas detector is introduced. The detector makes use of the very high catalytic activity of gold nanoparticles. Gold nanoparticles are deposited on the surfaces of an array of carbon nanotubes (CNTs). The CO gas is transformed into CO₂ as it comes in contact with the nanoparticles, and free electrons are released. The extra free electrons result in a measurable reduction in the resistivity of the CNT array. The detector has proved to be very sensitive at room temperature to CO gas concentrations as low as 100 parts per million. It is characterized by a very small size and can be easily powered with a battery.