• 文献标题:   Gate voltage enhances the thermoelectric transport of quantum dots in graphene nanoribbons
  • 文献类型:   Article
  • 作  者:   AMORIM FP, TORRES A, VILLEGAS CEP, ROCHA AR
  • 作者关键词:   thermoelectric transport, quantum dots in graphene, 7147 agnr, gate voltage enhance
  • 出版物名称:   COMPUTATIONAL MATERIALS SCIENCE
  • ISSN:   0927-0256 EI 1879-0801
  • 通讯作者地址:  
  • 被引频次:   0
  • DOI:   10.1016/j.commatsci.2023.112207 EA MAY 2023
  • 出版年:   2023

▎ 摘  要

Chemically derived graphene nanoribbons and quantum dots are unique nanostructures that offer more possibilities than 2D and 3D systems to tune their electronic properties due to the enhanced quantum confinement effects. This feature make them potential candidates for many technological applications, including thermoelectrics. In this work, we combined density functional theory calculations with the non -equilibrium Green's function formalism to investigate the electronic and thermoelectric properties of recently synthesized quantum dots in graphene nanoribbons under the presence of an applied gate voltage, and for different temperatures. We find that the electronic states at the band edge are highly localized in the inner region of the quantum dot, and can be lifted to higher energies by applying a gate voltage, which subsequently enhances figure of merit. Moreover, at zero gate voltage and room temperature, we estimate the lower bound for ZT to be approximately 0.25. Interestingly, this lower bound can exceed unity by smoothly increasing the gate voltage for values above 6 V. The overall results regarding the enhancement of ZT suggest that quantum dots in graphene nanoribbons would be promising candidates for thermoelectric applications.