First-principles investigation of electronic, optical, mechanical and heat transport properties of pentadiamond

A comparison with diamond

verfasst von

Bohayra Mortazavi, Fazel Shojaei, Xiaoying Zhuang, Luiz Felipe C. Pereira

Abstract

Pentadiamond is a carbon allotrope consisting of hybrid sp² and sp³ atoms, which has been predicted to be stable and synthesizable. In this work we employ first-principles calculations to explore the electronic structure, optical characteristics, mechanical response and lattice thermal conductivity of pentadiamond, performing a direct comparison with the corresponding properties in diamond. The HSE06 density functional predicts indirect electronic band gaps for pentadiamond and diamond with values of 3.58 eV and 5.27 eV, respectively. Results for optical characteristics reveal pentadiamond's large absorption in the middle UV region, where diamond does not absorb light, consistent with the smaller band gap of pentadiamond. The elastic modulus and tensile strength of pentadiamond are found to be 496 GPa and 60 GPa, respectively, considerably lower than the corresponding values for diamond. The lattice thermal conductivity is examined by solving the Boltzmann transport equation, with anharmonic force constants evaluated via state-of-the-art machine-learning interatomic potentials. We predict a thermal conductivity of 427 W/m-K for pentadiamond, less than one fifth of the corresponding quantity for diamond. Our results provide a useful vision of the intrinsic properties of pentadiamond, but also highlight some of its disadvantages in mechanical strength and heat conduction when compared to diamond.

Organisationseinheit(en)

Institut für Photonik
PhoenixD: Simulation, Fabrikation und Anwendung optischer Systeme

Externe Organisation(en)

Persian Gulf University
Universidade Federal de Pernambuco

Typ

Artikel

Journal

Carbon Trends

Band

3

Publikationsdatum

03.04.2021

Publikationsstatus

Veröffentlicht

Peer-reviewed

Ja

ASJC Scopus Sachgebiete

Werkstoffwissenschaften (sonstige), Werkstoffchemie, Chemie (sonstige)

Elektronische Version(en)

https://doi.org/10.1016/j.cartre.2021.100036 (Zugang: Offen)