Enhancement of electronic and thermoelectric properties of armchair bilayer graphene nanoribbons by chemical derivation and strain

Abstract

Because of decreasing lattice thermal conductivity of GNR by chemical derivation and strain, enhancement of the thermoelectric properties of electron part in the systems can be one of important methods in approach “phonon-glass electron-crystal” (PGEC). In this paper, we have suggested the synthesized hybrid systems formed by chemical derivation into middle parts of b-AGNRs, and then investigated the band structures and thermoelectric properties of electron part as function of out-layer strain and elastic strain along ribbon direction. The calculated results reveal that all hybrid systems are stable structurally and the band gaps of the systems increase remarkably from 0.04 to 1.59 eV under different strains. When the strain along periodical direction change 4 % and 12 %, the thermoelectric characteristics are noticeably enhanced than other strains. Especially, the systems formed by graphane exhibit the electronic figure of merit (ZTe) of 0.95. In the case of hc < h0, the dependence of the thermoelectric properties of electron part in hybrid b-AGNRs on the out-layer strain is insignificant.