Outstanding Thermal Conductivity of Single Atomic Layer Isotope-Modified Boron Nitride

Qiran Cai, Declan Scullion, Wei Gan, Alexey Falin, Pavel Cizek, Song Liu, James H. Edgar, Rong Liu, Bruce C. C. Cowie, Elton J. G. Santos, Lu Hua Li

Research output: Contribution to journalArticlepeer-review

Abstract / Description of output

Materials with high thermal conductivities (κ) are valuable to solve the challenge of waste heat dissipation in highly integrated and miniaturized modern devices. Herein, we report the first synthesis of atomically thin isotopically pure hexagonal boron nitride (BN) and its one of the highest κ among all semiconductors and electric insulators. Single atomic layer (1L) BN enriched with
11B has a κ up to 1009 W/mK at room temperature. We find that the isotope engineering mainly suppresses the out-of-plane optical (ZO) phonon scatterings in BN, which subsequently reduces acoustic-optical scatterings between ZO and transverse acoustic (TA) and longitudinal acoustic phonons. On the other hand, reducing the thickness to a single atomic layer diminishes the interlayer interactions and hence umklapp scatterings of the out-of-plane acoustic (ZA) phonons, though this thickness-induced κ enhancement is not as dramatic as that in naturally occurring BN. With many of its unique properties, atomically thin monoisotopic BN is promising on heat management in van der Waals devices and future flexible electronics. The isotope engineering of atomically thin BN may also open up other appealing applications and opportunities in 2D materials yet to be explored.
Original languageEnglish
Article number085902
JournalPhysical Review Letters
Volume125
Issue number8
DOIs
Publication statusPublished - 21 Aug 2020

Fingerprint

Dive into the research topics of 'Outstanding Thermal Conductivity of Single Atomic Layer Isotope-Modified Boron Nitride'. Together they form a unique fingerprint.

Cite this