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Novel, low-cost solid-liquid-solid process for the synthesis of α-Si3N4 nanowires at lower temperatures and their luminescence properties.

ABSTRACT: Ultra-long, single crystal, α-Si3N4 nanowires sheathed with amorphous silicon oxide were synthesised by an improved, simplified solid-liquid-solid (SLS) method at 1150 °C without using flowing gases (N2, CH4, Ar, NH3, etc.). Phases, chemical composition, and structural characterisation using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM/HRTEM), Fourier-transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS) showed that the nanowires had Si3N4@SiOx core-shell structures. The growth of the nanowires was governed by the solid-liquid-solid (SLS) mechanism. The room temperature photoluminescence (PL) and cathodoluminescence (CL) spectra showed that the optical properties of the α-Si3N4 nanowires can be changed along with the excitation wavelength or the excitation light source. This work can be useful, not only for simplifying the design and synthesis of Si-related nanostructures, but also for developing new generation nanodevices with changeable photoelectronic properties.

SUBMITTER: Liu H

PROVIDER: S-EPMC4660443 | biostudies-other | 2015

REPOSITORIES: biostudies-other

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