  Graphene is a true two dimensional material with exceptional electronic
properties and enormous potential for practical applications. Graphene's
promise as a chemical sensor material has been noted but there has been
relatively little work on practical chemical sensing using graphene, and in
particular how chemical functionalization may be used to sensitize graphene to
chemical vapors. Here we show one route towards improving the ability of
graphene to work as a chemical sensor by using single stranded DNA as a
sensitizing agent. The resulting broad response devices show fast response
times, complete and rapid recovery to baseline at room temperature, and
discrimination between several similar vapor analytes.
