Studies on spontaneous formation of 1D nanocrystals of silicon carbide

Abstract

Novel nanostructures have been formed spontaneously during the thermolysis of mixtures containing halogenohydrocarbons and Si-related compounds as a reducing agent in a calorimetric bomb. Elemental analysis, XRD (X-Ray Diffraction), EELS (Electron Energy Loss Spectroscopy), EDX (Energy Disspersive X-ray spectroscopy), IR (InfraRed spectroscopy), Raman spectroscopy, HR SEM (High Resolution Scanning Electron Spectroscopy) and TEM (Transmission Electron Spectroscopy) were used to determine the chemical composition and structural features of the products. They contain well-crystallized elongated 1D single crystals of SiC nanofibres, coated with a thin SiO 2 amorphous layer, and crystallized carbon nanoparticles.

Scanning tunneling microscopy investigations of silicon carbide nanowires

“…The 3C cubic zincblende structure (also known as the b-SiC) has been confirmed as a dominant polytype for SiC nanowires and also for the ones obtained in combustion synthesis [15]. The nanofibres' axis lies usually in the [1 1 1] direction but the objects with [1 0 0] orientation have been also observed [7].…”

Synthesis of Silicon Carbide Dendrite by the Arc Plasma Process and Observation of Nanorod Bundles in the Dendrite Arm

“…4(b). Because electron diffraction streaks are always perpendicular to growth direction, [19][20][21][22][23][24][25][26] it may be evident from the SAED that stacking planes are {111} and growth direction of nanorods in the dendrite arm is [111]. All the nanorods in the bundles or bunches, are seen to be aligned in the same direction.…”

Combustion synthesis of one‐dimensional nanocrystalline silicon carbide

“…Contrary to this, the nanocrystalline SiC samples have a Raman band at 900 cm -1 . This feature could be affected by finite size effect in nanocrystalline samples and may also suggest the presence of multiple politypes of SiC [7].…”

“…While the total duration (including a heat-up of reaction promoter) was ca 1.5 s, the main combustion period lasted 0.36 s only. Following the procedure outlined earlier [7], the emission spectrum was recorded during the reaction and the nearly blackbody radiation revealed that the average temperature during the combustion was within 1800 ± 100 K. As a matter of fact, the high-temperature direct synthesis of SiC from the elements is postulated [9,10] to occur in the same temperature range. The de-fluorination of PTFE using Si elemental is strongly dependent on the initial pressure and combustion atmosphere [8].…”

“…Here we propose a versatile, fast, one-step autothermal reaction to produce SiCNWs via SHS route which is known to produce many useful compounds [6]. We have already reported the formation of onedimensional SiC nanometric structures through the reductive de-fluorination of PTFE with silicon-bearing compounds [7,8]. In this paper we present the results shedding light on the SiCNWs growth mechanism according to the general reaction scheme represented by 2…”