New types of chemical sensors for environmental monitoring, food safety or security applications could be based on nanotechnology, according to an assistant professor of Chemistry at UC Davis University, Prof. Osterioh.
"Nanomaterials are well suited to chemical sensor applications, because their chemical properties vary quite a bit in response to changes that occur in their chemical environment," says Osterioh. Osterloh and his team have discovered that nanowires made with lithium, molybdenum and selenium atoms produce changes in electrical resistance of up to 200 percent when exposed to organic solvent vapors. When nanowires are deposited between two conductors, a simple chemical sensor is formed.
By adding chemical groups to the nanowires, the researchers were able to modify the sensor to measure the acidity of a solution. The team is currently investigating whether this "programming" property can be extended to make it possible to use sensors to detect explosives or other hazards such as environmental contamination (for example lead in drinking water).
The work was presented at the annual meeting of the American Chemical Society in Philadelphia last week.