Structural characterization of SiC nanoparticles

Abstract

The structure and size of SiC nanoparticles were studied by different characterization methods including small angle X-ray scattering (SAXS), transmission electron microscope (TEM), and X-ray diffraction (XRD). The results showed that particle size distributions determined respectively from SAXS and TEM are comparable and follow the log-normal function. The size distribution of the particles is between 10 to 100 nm with most of them being in the range of 20–50 nm. The average particle size is around 42 nm. XRD identifies the phase of the SiC nanoparticles and suggests the average size of the single crystalline domain to be around 21 nm. The combined results from XRD and SAXS suggest the existence of many polycrystals, which is confirmed by the HRTEM observation of particles with twins and stacking faults. The material synthesis methods leading to various particle sizes are also discussed.

All Screen Printed and Flexible Silicon Carbide NTC Thermistors for Temperature Sensing Applications

“…The X-ray diffraction (XRD) patterns of the commercially purchased SiC particles validate their cubic crystalline nature, exhibiting well-defined and sharp diffraction peaks, as depicted in Figure 4a. The peaks observed at 2θ = 39.6°, 42°and 71.2°correspond to the 002, 200 and 311 crystalline planes of the 3C − SiC cubic crystal structure, consistent with the (International Centre for Diffraction Data) ICDD card: 04-002-9070 [53,54]. Additionally, the presence of 2H − SiC peaks at 2θ = 45°(015) and 49°(016), as per the ICDD card: 04-008-2392 [55], may potentially be attributed to a blending of the two phases formed during the nanoparticle fabrication process [56].…”

Facile Synthesis of Highly Defected Silicon Carbide Sheets for Efficient Absorption of Electromagnetic Waves

“…The SF peaks of the defect-free SiC exhibit an inexistent peak. Most of the reported SiC materials with high SF density show a nanowire morphology and SF density below 3.21. ,− Surprisingly, the SiC sheets derived from paper, in this work, contain an extremely high density of SFs. The SF densities of the SiC sheets at 1400, 1500, and 1600 °C are 3.87, 6.05, and 12.55, respectively, and the SiC sheet produced at 1600 °C demonstrates over fourfold enhancements in SF content compared with previously reported SiC materials.…”

“…EM wave attenuation is believed to be strongly affected by the presence of a high SF density in the SiC domain. However, although many studies have focused on the effects of SFs within SiC, the density of SFs in previously reported SiC materials generally falls below 3.21, ,− far lower than the requirements of most applications. Furthermore, because of the use of multiwalled carbon nanotubes as the source material, producing SiC with SFs is expensive, costing about $1000 to obtain a kilogram of the carbide.…”