Microstructural and compositional characterization of a new silicon carbide nanocables using scanning transmission electron microscopy

Abstract

Composite nanocables with peculiar structure were synthesized using a solid–liquid–solid mechanism. Each of the nanocables consists of a crystalline core sheathed with an amorphous layer ( 40 nm in average diameter). The crystalline core of the nanocables is so fine (1– 6 nm in diameter), that it is nearly impossible to characterize them using other methods. Fortunately, the powerful high resolution electron energy loss spectroscopy (EELS) technique (with minimum beam size <1 nm ) allowed us to analyze this peculiar nanomaterial. The fine crystalline core was proved to be a hexagonal silicon carbide, while the sheathing layer was silicon oxide. High angle dark field technique was employed to map the nanocable structures. Our results show that the EELS is powerful in nanometric regime characterization, while the SiC nanocables reported here may be useful in future nanotechnology.