The new sensors are based on binary metal oxide nanocomposites. These provide enhanced sensitivity to detect environmental pollutants and chemical weapons, where the potential terror threat is poisonous gas.
The advantage of using a binary metal oxide sensor is that one of the components provides a high density of conductive electrons, and the second component is a strong catalyst. To effectively detect and analyse a gas an electron donor and a substance “accommodating” the reaction are required. This allows the sensors to discriminate between very low concentrations of analytes, thereby detecting and characterizing the gas.
The new sensor also functions very quickly. This is helped through the formation of chemisorption centers. These are chemically active spots on the nanocrystals, designed to facilitate gas molecule adsorption.
Discussing the sensor further in a research briefing, the lead scientist Professor Leonid Trakhtenberg explains the importance of the work: “Choosing the right sensor composition can make a device at least ten times more effective and enable an exceptionally fast response, which is crucial for preventing terrorist attacks.”
As well as terrorist threats, the new sensors could be further used for sensing of atmospheric pollutants such as nitrogen dioxide. This gas is emitted from car exhausts and it can have a significant effect on public health.
A future stage of the research is to consider if nanofibers can be incorporated. These could enhance the sensing mechanisms still further.
The sensor has been designed through a joint project involving scientists from the Semenov Institute of Chemical Physics of the Russian Academy of Sciences and the Moscow Institute of Physics and Technology (MIPT). The research findings are reported to the journal Sensors and Actuators B: Chemical, with the research paper headed “The mechanisms of sensory phenomena in binary metal-oxide nanocomposites”.
