Thermoelectric properties of graphene nanoribbons with surface roughness

Abstract

We theoretically investigate the ballistic thermoelectric performance of graphene nanoribbons with surface roughness using the nonequilibrium Green's function method. The results show that the surface roughness could dramatically reduce the thermal conductance of graphene nanoribbons, and thus lead to the boosting of thermoelectric performance of graphene (the figure of merit can be as high as 3.7 at room temperature). Meanwhile, the electron transport properties of different edged rough graphene nanoribbons exhibit distinctive anisotropic behaviors, i.e., the thermal power of armchair edged nanoribbons significantly increases, while that of zigzag edged remains nearly unchanged, which is mainly attributed to the edge effect. The findings presented in this paper qualify surface roughness as an efficient approach to enhance the thermoelectric performance of graphene nanoribbons.

KAgX (X = S, Se): High-Performance Layered Thermoelectric Materials for Medium-Temperature Applications

“…This unique arrangement of atoms is conducive to its structural stability. Optimized lattice parameters a / b equal to 4.29 and 4.50 Å for 2D KAgS and KAgSe, respectively, which is consistent with previous theoretical reports. , In addition, their peculiar atomic structure and conspicuously plicated configuration of the surface greatly enhances the phonon scattering, benefiting to block heat transport . More details and calculated coefficients are given in Table .…”

“…35,36 In addition, their peculiar atomic structure and conspicuously plicated configuration of the surface greatly enhances the phonon scattering, benefiting to block heat transport. 50 More details and calculated coefficients are given in Table 1.…”

Significant enhancement of the thermoelectric properties of CaP3 through reducing the dimensionality

“…As shown in Fig. 1(c), we can see clearly that it exhibits rough surface and boundary, which would greatly enhancing the phonon scattering 46 . For bulk, it also has P-1(No.2) symmetry as the monolayer, and can be viewed as phosphorus dimer with the insertion into of calcium atoms at vacancy sites.…”

Thermodefect voltage in graphene nanoribbon junctions

“…With the advancement of nanotechnology, it is nowadays possible to engineer a variety of defects in GNRs using tailored electron beam exposure technique [34][35][36][37][38]. The already realized possibilities of engineering the disorderness [39][40][41][42][43][44][45][46] clearly improves the potential of the present work.…”