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Title: Optimal thickness of silicon membranes to achieve maximum thermoelectric efficiency: A first principles study

Abstract

Silicon nanostructures with reduced dimensionality, such as nanowires, membranes, and thin films, are promising thermoelectric materials, as they exhibit considerably reduced thermal conductivity. Here, we utilize density functional theory and Boltzmann transport equation to compute the electronic properties of ultra-thin crystalline silicon membranes with thickness between 1 and 12 nm. We predict that an optimal thickness of ∼7 nm maximizes the thermoelectric figure of merit of membranes with native oxide surface layers. Further thinning of the membranes, although attainable in experiments, reduces the electrical conductivity and worsens the thermoelectric efficiency.

Authors:
 [1];  [2];  [3];  [4];  [3]
  1. Max Planck Institut für Polymerforschung, Ackermannweg 10, D-55128 Mainz (Germany)
  2. Department of Aerospace Engineering Sciences, University of Colorado Boulder, Boulder, Colorado 80309 (United States)
  3. (Germany)
  4. Department of Chemistry, University of California Davis, One Shields Ave., Davis, California 95616 (United States)
Publication Date:
OSTI Identifier:
22594405
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 5; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; BOLTZMANN EQUATION; DENSITY FUNCTIONAL METHOD; EFFICIENCY; ELECTRIC CONDUCTIVITY; LAYERS; MEMBRANES; NANOWIRES; OXIDES; SILICON; THERMAL CONDUCTIVITY; THERMOELECTRIC MATERIALS; THICKNESS; THIN FILMS

Citation Formats

Mangold, Claudia, Neogi, Sanghamitra, Max Planck Institut für Polymerforschung, Ackermannweg 10, D-55128 Mainz, Donadio, Davide, E-mail: ddonadio@ucdavis.edu, and Max Planck Institut für Polymerforschung, Ackermannweg 10, D-55128 Mainz. Optimal thickness of silicon membranes to achieve maximum thermoelectric efficiency: A first principles study. United States: N. p., 2016. Web. doi:10.1063/1.4960197.
Mangold, Claudia, Neogi, Sanghamitra, Max Planck Institut für Polymerforschung, Ackermannweg 10, D-55128 Mainz, Donadio, Davide, E-mail: ddonadio@ucdavis.edu, & Max Planck Institut für Polymerforschung, Ackermannweg 10, D-55128 Mainz. Optimal thickness of silicon membranes to achieve maximum thermoelectric efficiency: A first principles study. United States. doi:10.1063/1.4960197.
Mangold, Claudia, Neogi, Sanghamitra, Max Planck Institut für Polymerforschung, Ackermannweg 10, D-55128 Mainz, Donadio, Davide, E-mail: ddonadio@ucdavis.edu, and Max Planck Institut für Polymerforschung, Ackermannweg 10, D-55128 Mainz. 2016. "Optimal thickness of silicon membranes to achieve maximum thermoelectric efficiency: A first principles study". United States. doi:10.1063/1.4960197.
@article{osti_22594405,
title = {Optimal thickness of silicon membranes to achieve maximum thermoelectric efficiency: A first principles study},
author = {Mangold, Claudia and Neogi, Sanghamitra and Max Planck Institut für Polymerforschung, Ackermannweg 10, D-55128 Mainz and Donadio, Davide, E-mail: ddonadio@ucdavis.edu and Max Planck Institut für Polymerforschung, Ackermannweg 10, D-55128 Mainz},
abstractNote = {Silicon nanostructures with reduced dimensionality, such as nanowires, membranes, and thin films, are promising thermoelectric materials, as they exhibit considerably reduced thermal conductivity. Here, we utilize density functional theory and Boltzmann transport equation to compute the electronic properties of ultra-thin crystalline silicon membranes with thickness between 1 and 12 nm. We predict that an optimal thickness of ∼7 nm maximizes the thermoelectric figure of merit of membranes with native oxide surface layers. Further thinning of the membranes, although attainable in experiments, reduces the electrical conductivity and worsens the thermoelectric efficiency.},
doi = {10.1063/1.4960197},
journal = {Applied Physics Letters},
number = 5,
volume = 109,
place = {United States},
year = 2016,
month = 8
}
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