Percolation gas sensor demonstrator
PI: Martin Castell
Department: Materials
The requirement for gas sensing instrumentation is steadily growing, and predicted to exceed a market size of $2.5b by 2020. Much of this growth is driven by increasing enforcement of health and safety regulations. The cheapest and most prevalent types of device are electrochemical sensors that change their electrical characteristics as a function of the amount of analyte in the environment. The main drawback with these sensors is that their sensitivity is poor, so they are not able, for example, to compete with the olfactory sense of a trained sniffer dog for explosives vapour detection.
For the last eight years we have been working on developing a new type of electrochemical sensor that is both cheap and highly sensitive. The high sensitivity arises by creating a conducting polymer network that operates at the electrical percolation threshold, and we therefore call our new technology "percolation sensors". We have so far demonstrated in the lab a limit of detection of 34 parts per billion of ammonia, which far exceeds the equivalent sensitivity of a conventional thin film sensor. Not only might our new technology act as a rival to existing electrochemical sensor designs, it might also broaden the application base because of the higher sensitivity e.g. sensors used for disease detection through human breath monitoring, explosives vapour detection sensors at airports, or sensors used in the industrial internet of things.
In this IAA project we intend to turn our lab-based device into a stand-alone demonstrator. This will serve two functions. The first is to allow potential investors and industrial collaborators to see that the sensor can be packaged into a small working unit ready for commercialisation. The second is to allow our partners to test the device for explosives vapour sensing.