Enhanced gas-flow-induced voltage in graphene

We find experimentally that gas-flow-induced voltage in monolayer graphene is more than twenty times of that in bulk graphite. Examination over samples with sheet resistances ranging from 307 to 1600 Omega/sq shows that the induced voltage increases with the electric resistance and can be further improved by controlling the quality and doping level of graphene. The induced voltage is nearly independent of the substrate materials and can be well explained by the interplay of Bernoulli's principle and the carrier density dependent Seebeck coefficient. The results demonstrate that graphene has great potential for flow sensors and energy conversion devices. (C) 2011 American Institute of Physics. [doi:10.1063/1.3624590]