Ethanol sensor
Researchers at the Karlsruhe Institute of Technology (KIT; www.kit.edu) and the Technical University of Darmstadt (both Germany; www.tu-darmstadt.de) have developed a new sensor for gas molecules that responds selectively to ethanol, but not other alcohols or humidity. Described in a recent issue of Advanced Materials, this new class of sensor is based on the combination of sensitive graphene transistors with a customized metal-organic framework (MOF) grown on the surface. MOFs consist of metallic nodes and organic molecules as connecting rods. By choosing various combinations, these highly porous crystalline materials can be tailored to different applications to reach a selective absorption capacity for certain molecules, for instance. The researchers from Karlsruhe and Darmstadt presented a selective sensor platform by growing a surface-mounted metal-organic framework (SURMOF) directly on a graphene field-effect transistor (GFET). Such a component profits from the high sensitivity and simple read-out of a GFET, as well as from the high selectivity of a SURMOF.