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Title: Thermal conductivity of hexagonal BC 2 P – a first-principles study
In this work, we report a high thermal conductivity ( k ) of 162 W m −1 K −1 and 52 W m −1 K −1 at room temperature, along the directions perpendicular and parallel to the c -axis, respectively, of bulk hexagonal BC 2 P (h-BC 2 P), using first-principles calculations. We systematically investigate elastic constants, phonon group velocities, phonon linewidths and mode thermal conductivity contributions of transverse acoustic (TA), longitudinal acoustic (LA) and optical phonons. Interestingly, optical phonons are found to make a large contribution of 30.1% to the overall k along a direction perpendicular to the c -axis at 300 K. BC 2 P is also found to exhibit high thermal conductivity at nanometer length scales. At 300 K, a high k value of ∼47 W m −1 K −1 is computed for h-BC 2 P at a nanometer length scale of 50 nm, providing avenues for achieving efficient nanoscale heat transfer.  more » « less
Award ID(s):
1847129
PAR ID:
10211478
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
RSC Advances
Volume:
10
Issue:
70
ISSN:
2046-2069
Page Range / eLocation ID:
42628 to 42632
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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