Search for high thermal conductivity materials among boron/carbon/nitrogen compounds*

The Slack guidelines [1] suggest that materials with complex crystal structures should not have high thermal conductivity. However, an exception to this rule was recently identified in BC₂N, which was predicted to achieve a room temperature thermal conductivity of around 1000-2000 W m^-1 K^-1 in the trigonal structure [2, 3]. Moreover, recent work suggests that ultrahigh thermal conductivity may not be possible in compounds that do not contain boron (B), carbon (C) or nitrogen (N) [4]. Motivated by these findings, we present results of a first principles-based computational search for high thermal conductivity among several hundred compounds composed of combinations of B, C, and N. The relatively low thermal conductivities of the studied compounds highlight the challenges in satisfying the stringent high thermal conductivity criteria among real materials.
[1] G. A. Slack, J. Phys. Chem Solids, 34, 321 (1973).
[2] S. Ju, et al. https://doi.org/10.26434/chemrxiv.9850301.v1
[3] S. N. Sadeghi, S.M. V. Allaei, M. Zebarjadi and K. Esfarjani, J. Mat Chem. C (2020).
[4] N. Ravichandran and D. Broido, Phys. Rev. X 10, 021063 (2020).