November 23, 2007—A tiny “electronic nose” that Massachusetts Institute of Technology (MIT) researchers have engineered with a novel inkjet printing method could be used to detect hazards including carbon monoxide, harmful industrial solvents and explosives.
Led by MIT professor Harry Tuller, the researchers have devised a way to print thin sensor films onto a microchip, a process that could eventually allow for mass production of highly sensitive gas detectors.
The prototype sensor, created by Tuller, postdoctoral fellow Kathy Sahner and graduate student Woo Chul Jung, members of MIT’s Electroceramics Group in MSE, consists of thin layers of hollow spheres made of the ceramic material barium carbonate, which can detect a range of gases. Using a specialized inkjet print head, tiny droplets of barium carbonate or other gas-sensitive materials can be rapidly deposited onto a surface, in any pattern the researchers design.
The miniature, low-cost detector could be used in a variety of settings, from an industrial workplace to an air-conditioning system to a car’s exhaust system, according to Tuller. “There are many reasons why it’s important to monitor our chemical environment,” he said.
For a sensor to be useful, it must be able to distinguish between gases. For example, a sensor at an airport would need to know the difference between a toxic chemical and perfume, Tuller said. To achieve this, sensors should have an array of films that each respond differently to different gases. This is similar to the way the human sense of smell works, Tuller explained.
The research is funded by the National Science Foundation. For more information, see the NSF Web site.
