Scientists from the Delft University of Technology and the University of Duisburg-Essen have pioneered a system of utilizing graphene in order to identify noble gasses, according to Graphene Info. Because of the chemically passive nature of these gasses, the detection of them is extremely difficult.
Because of graphene’s atomic thickness, it is a perfect filter material for gasses and liquids. Additionally, graphene is one of the strongest materials known as capable of withstanding high stresses. These two traits are perfect for the next generation of gas sensors.
The basis of this system is scientists using microscopic balloons made of bilayer graphene, with very minimal nanopore perforations in order to detect gases. TU Delft researcher Irek Rosłoń describes it as follows:
“We measure the time it takes the balloon to deflate. At such a small scale, this happens very quickly—within around 1/100.000th of a second—and interestingly, the length of time depends strongly on the type of gas and the size of the pores. For example helium, a light gas with high molecular velocity escapes five times faster than krypton, a heavy and slowly-moving gas.”.
The mass and molecular velocity of the gases allow for the distinguishing of different gases within these balloons. The researchers are additionally attempting to extend this idea to study gas flow through nano-channels, making it more difficult for gas to escape.
This work could allow for low cost, low profile sensors at commercial levels in the future.