Facile synthesis of vertically aligned hexagonal boron nitride nanosheets hybridized with graphitic domains

Abstract

Motivated by the recent quest for producing novel two dimensional nanomaterials, we developed a facile synthetic method for growing boron nitride–carbon (BN–C) phase-separated composite nanosheet coatings on silicon/silicon dioxide (Si/SiO2) substrates. The coatings were composed of compact partially vertically aligned nanosheets with a nanoscale roughness. The majority of the obtained BN–C nanosheets were less than 5 nm in thickness, mostly consisting of 2–15 atomic layers. Electron energy loss spectroscopy, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy revealed the natural sp2 hybridization of the product, and cathodoluminescence spectroscopy measurements showed strong luminescence emission in the ultraviolet region at room temperature. Ultraviolet-visible spectroscopy demonstrated that the composite structure of alternating BN and C domains has different optical band gap features compared to pure h-BN nanosheets and graphenes, making it a promising material for further fundamental physical studies and potential applications in optoelectronics. Moreover, due to the rough morphology and nanoscale features of the BN–C coatings, they exhibited excellent water repellency (superhydrophobicity).