A Theoretical Study on the Thermoelectric Properties of Porous Armchair Germanene NanoribbonsAuthor : Varunpreet Kaur, Deep Kamal Kaur Randhawa and Sukhdeep Kaur
Volume 8 No.2 April-June 2019 pp 42-49
Since the limits of conventional sources of energy are rapidly approaching, the thermoelectric devices have attracted attention for their potential of power generation directly from waste heat. In this paper, thermoelectric properties of porous armchair Germanene nanoribbons (AGeNRs) have been explored for a range of pore dimensions in order to achieve a high performance two-dimensional nanoscale thermoelectric device. The work has been done to investigate the influence of different nanopore shapes and their associated positions on the thermoelectric performance so as to tune it to the optimum pore shape and position that would enhance the overall thermoelectric efficiency. Also, the effect of passivation of the pore edges on thermoelectric parameters for all shapes has been studied. Further, the influence of temperature dependence on figure of merit has been observed. Ballistic transport regime and semi-empirical method using Huckel basis set is used to obtain the electrical properties while the Brenner potential is used for the phononic properties.
Thermoelectric, Nanoribbon, Figure of Merit, Nanopore, Thermal Conductivity
 Daniel D. Pollock, Thermoelectricity; Theory, Thermometry, Tool, Philadelphia, ASTM Special Technical Publication 852, 1985.
 G.S. Nolas, J. Sharp, and H.J. Goldsmid, “Thermoelectrics: Basic principles and new materials developments”, Springer series in Material Science., Berlin, Heidelberg: Springer, Vol. 45, 2001.
 H.J. Goldsmid, Ed.1, “Introduction to Thermoelectricity”, Springer Series in Material Science., Berlin: Springer, Vol. 121, pp. 250, 2010.
 H. Şahin, S. Cahangirov, M. Topsakal, E. Bekaroglu, E. Akturk, and R. T. Senger, “Monolayer honeycomb structures of group-IV elements and III-V binary compounds: First- principles calculations”, Physical Review B., Vol. 80, pp. 155453, Oct. 2009.
 M. M. Monshi, S. M. Aghaei and I. Calizo, “Edge functionalized germanene nanoribbons: impact on electronic and magnetic properties”, RCS advances, Vol. 7, pp. 18900-18908, March 2017.
 N. J. Roome, and J. D. Carey, “Beyond graphene: stable elemental monolayers of silicene and germanene”, ACS applied materials & interfaces, Vol. 6, pp. 7743-7750, 2014.
 J. Yan, R. Stein, D.M. Schaefer, Xiao-Qian Wang, and M. Y. Chou, “Electron- Phonon Coupling in Two-Dimensional Silicene and Germanene”, Physical Review B., Vol. 88, 121403, August 2013.
 Z. Ni, Q. Liu, K. Tang, and J. Zheng et al., “Tunable Bandgap in Silicene and Germanene”, Nano Letters 2012, Vol. 12, pp. 113–118, Nov. 2011.
 T. Y. Ng, J. Yeo, and Z. Liu, “Molecular dynamics simulation of the thermal conductivity of short strips of graphene and silicene: a comparative study”, Int J Mech Mater Des., Vol. 9, No. 2, pp. 105-114, June 2013.
 Y. Wang, J. Zheng, and Z. Ni et al., “Half-Metallic Silicene and Germanene Nanoribbons: towards High-Performance Spintronics Device”, NANO: Brief reports and reviews, Vol. 7, No. 5, pp. 1250037(1-9), April 2013.
 F. Bechstedt, L. Matthes, P. Gori and O. Pulci, “Infrared absorbance of silicone and germanene”, Applied Physics Letter., Vol. 100, 261906, June 2012.
 M.A. Balateroa, G. J. Paylagab, N. T. Paylagac, and R. V. Bantaculod, “Molecular Dynamics Simulations of Thermal Conductivity of Germanene Nanoribbons (GeNR) with Armchair and Zigzag Chirality”, Applied Mechanics and Materials, Vol. 772, pp. 67-71, April 2015.
 G. Baskaran, Room Temperature Superconductivity, Spin Liquid and Mott Insulator: Silicene and Germanene as prospective playgrounds, September, 2013.
 K. Yang, S. Cahangirov, A. Cantarero, A. Rubio, and R. D’Agosta, “Thermoelectric properties of atomic-thin silicene and germanene nano-structures”, Physical Review B., Vol. 89, pp. 125403, October 2013.
 M. Houssaa, B. Broeka, E. Scalisea, G. Pourtoisb, V.V Afanas’eva, and A. Stesmansa, “Theoretical Study of Silicene and Germanene”, ECS Transactions., Vol. 53, No. 1, pp. 51-62, May 2013.
 M.S. Hossain, F.A. Dirini, F.M. Hossain, and E. Skafidas: “High-performance graphene nano-ribbon thermoelectric devices by incorporation and dimensional tuning of nanopores”, Sci. Rep., Vol. 5, 11297, June 2015.
 L. D. Hicks, and M. S. Dresselhaus, “Effect of quantum-well structures on the thermoelectric figure of merit”, Phys. Rev. B., Vol. 47, pp. 12727, May 1993.
 S. Kaur, S. B. Narang and D. K. Randhawa, “Influence of the pore shape and dimension on the enhancement of thermoelectric performance of graphene nanoribbons”, Journal of Materials Research., Vol. 32, pp. 1149-1159, Dec. 2016.
 S.M. Aghaei, M.M. Monshi, I. Torres, M. Banakermani, and I. Calizo, “Lithium-functionalized germanene: A promising media for CO2 capture”, Physics Letters A., Vol. 382, pp. 334-338, Feb. 2018.
 D. Kienle, J.I. Cerda, and A.W. Ghosh, “Extended Huckel Theory for band structure, chemistry, and transportI. Carbon nanotubes”, Journal of Applied Physics, Vol. 100, 043714, August 2006.
 M.S. Hossain, F. Al-Dirini, F.M. Hossain, and E. Skafidas, “High performance graphenenano-ribbon thermoelectric devices by incorporation and dimensional tuning of nanopores”, Sci. Rep., Vol. 5, 11297, June 2015.
 K. Esfarjani, M. Zebarjadi, and Y. Kawazoe, “Thermoelectric properties of a nanocontact made of two-capped single-wall carbon nanotubes calculated within the tight-binding approximation”, Phys. Rev. B: Condens. Matter Mater. Phys., Vol. 73, pp. 403-406, Feb.2006.
 R. Landauer, “Spatial variation of currents and fields due to localized scatterers in metallic conduction”, IBM. J. Res. Dev., Vol. 1, pp. 223, July 1957.
 K. Stokbro, D.E. Petersen, S. Smidstrup, A. Blom, M. Ipsen, and K. Kaasbjerg, “Semiemperical model for nanoscale device simulations”, Phys. Rev. B:Condens. Matter Mater. Phys., Vol. 82, 075420, August 2010.
 J.H. Chen, C. Jang, S. Xiao, M. Ishigami, and M.S. Fuhrer, “Intrinsic and extrinsic performance limits of graphene devices on SiO2”, Nat. Nano., Vol. 3, pp. 206-209, April 2008.
 L. Pan, H.J. Liu, X.J. Tan, H.Y. Lv, J. Shi, X.F. Tang, and G. Zheng, “Thermoelectric properties of armchair and zigzag silicone nanoribbons”, Physical Chemistry Chemical Physics, Vol. 14, pp. 13588– 13593, July 2012.
 L.Hu, and D. Maroudas, “Thermal transport properties of grapheme nanomeshes”, Journal of Applied Physics, Vol. 116, 184304, Oct. 2014.