  We have combined DFT calculations with the Boltzmann semiclassical transport
theory to investigate the effect of selective hydrogenation on the
thermoelectric properties of tetra-penta-deca-hexagonal graphene (TPDH-gr), a
recently proposed new 2D carbon allotrope. Our results show that the Seebeck
coefficient is enhanced after hydrogenation. The conductivity along the x
direction is increased almost eight times while being almost suppressed along
the y direction. This behavior can be understood in terms of the electronic
structure changes due to the appearance of a Dirac-like cone after the
selective hydrogenation. Consistent with the literature, the electronic
contribution to thermal conductivity displays the same qualitative behavior as
the conductivity, as expected from the Wiedemann-Franz law. The increase in
thermal conductivity with temperature limits the material's power factor. The
significant increase in the Seebeck coefficient and conductivity increases also
contribute to the thermal conductivity increase. These results show that
hydrogenation is an effective method to improve the TPDH-gr thermoelectric
properties, and this carbon allotrope can be an effective material for
thermoelectric applications.
