  Monolayer graphene shows Seebeck coefficient several times and
gas-flow-induced voltage twenty times higher than that of bulk graphite. Here
we find that the Seebeck coefficient of multilayer graphene increases
monotonically with increasing layer and reaches its peak value at hexa-layer
~77% higher than for monolayer and then decreases, although the electric
resistance decreases monotonically with increasing layer. The flow-induced
voltage is significantly higher in 2, 4, 5, 6, 7 layered graphene than in 1, 3,
8 layered one, against the prevailing view that it should be proportional to
Seebeck coefficient. These thickness effects are also in sharp contrast to that
in continuous aluminum nanofilms.
