| Abstract Scope |
B4C is an excellent high temperature thermoelectric material with a melting temperature of 2763 oC, Seebeck coefficient in the range of 100-300 μV/K and an extremely high hardness. In order to examine it’s stability, properties and thus application in the 2-D form, we employ van der Waals corrected density-functional theory to compute the formation energies of non-polar 2-D slabs of B4C cleaved along multiple directions. We find that the formation energies of the various slabs are similar, indicating lack of significant preference for a cleavage direction. For instance, B4C cleaved along (001), (012) and (101) planes have formation energies of 0.056 eV/atom, 0.105 eV/atom and 0.116 eV/atom, respectively, which are all below the threshold of 0.2 eV/atom where free-standing 2-D sheets are expected to be thermodynamically stable. We finally compute the thermoelectric coefficients of the 2-D slabs and preliminary results indicate that they perform as well as the bulk B4C. |