Scientists at the Naval Research Laboratory have developed a
vapor sensor based on new monolayer materials that show great potential for
future nanoscale electronic devices. NRL scientists have fabricated this sensor
using a single monolayer of molybdenum disulfide (MoS2) on a silicon dioxide
wafer. They show that it functions effectively as a chemical vapor sensor,
exhibiting highly selective reactivity to a range of analytes, and providing
sensitive transduction of transient surface physisorption events to the
conductance of the monolayer channel. The high surface-to-volume ratio of such
new two-dimensional materials is a significant asset for vapor sensor
applications—these materials must exhibit a rapid and selective response to a
range of analytes (determined by the character of surface atomic sites),
sensitive transduction of the perturbation to the electrical resistance of the
channel, and rapid recovery upon removal of the vapor