C and O doped BN nanoflake and nanowire hybrid structures for tuneable photoluminescence

Abstract

C and O doped BN nanoflakes and hybrid nanoflake-nanowire structures were synthesized in N2+H2environment using plasma-enhanced hot filament chemical vapour deposition with solid B4C as boron and carbon precursor. Structure and chemical composition of the C and O doped BN nanoflakes and hybrid nanoflake-nanowire hybrid structures were systemically studied using advanced characterization instruments including high resolution transmission electron microscope, micro-Raman spectroscope, Fourier transform infrared spectroscope, X-ray diffractometer, field emission scanning electron microscope, and X-ray photoelectron spectroscope. The obtained results evidence that the C and O doped BN nanowires nucleate and grow directly on the tops of C and O doped BN nanoflakes due to the presence of dangling bonds on the surfaces of tips of C and O doped BN nanoflakes, which were formed by the ion bombardment in plasma. The photoluminescence (PL) properties of C and O doped BN nanoflakes and C and O doped BN nanoflake-nanowire hybrid structures were studied at room temperature using a micro-Raman system with the 325 nm line of He-Cd laser as the excitation source. The results of PL measurements indicate that the PL properties of C and O doped BN nanoflake-nanowire hybrid structures significantly change with the length of C and O doped BN nanostructures due to the interface zones caused by the nanowire length. Thus, the PL properties can be efficiently tuned by the length of nanowires. These achievements can contribute to the synthesis of novel BN-based hybrid nanostructures and the development of the next generation BN-based optoelectronic nanodevices.