  We present first principles study of thermoelectric transport properties of
sandwiched heterostructure of Graphene (G)/hexagonal Boron Nitride (BN)/G,
based on Boltzmann transport theory for band electrons using the bandstructure
calculated from the Density Functional Theory (DFT) based plane-wave method.
Calculations were carried out for three, four and five BN layers sandwiched
between Graphene layers with three different arrangements to obtain the Seebeck
coefficient and Power factor in $T\sim 25-400$K range. Moreover, using
Molecular Dynamics (MD) simulations with very large simulation cell we obtained
the thermal conductance ($K$) of these heterostructures and obtained finally
the Figure-of-Merit ($ZT$). These results are in agreement with recently
reported experimental measurements.
