High thermal conductivity of suspended few-layer hexagonal boron nitride sheets

The thermal conduction of suspended few-layer hexagonal boron nitride (h-BN) sheets was experimentally investigated using a noncontact micro-Raman spectroscopy method. The first-order temperature coefficients for monolayer (1L), bilayer (2L) and nine-layer (9L) h-BN sheets were measured to be −(3.41 ± 0.12) × 10⁻², −(3.15 ± 0.14) × 10⁻² and −(3.78 ± 0.16) × 10⁻² cm⁻¹·K⁻¹, respectively. The room-temperature thermal conductivity of few-layer h-BN sheets was found to be in the range from 227 to 280 W·m⁻¹·K⁻¹, which is comparable to that of bulk h-BN, indicating their potential use as important components to solve heat dissipation problems in thermal management configurations.[Figure not available: see fulltext.]