Nanowires silicon carbide

Gundiah. G.. Madhav. G. V. Govindaraj. A. Rao, C. N. R. Synthesis and characterization of silicon carbide, silicon oxynitride and silicon nitride nanowires. J. Mater. Chem. 2002 12. 1606-1611. 

Zhao[266] demonstrated the successful synthesis of highly ordered mesoporous silicon carbides with unusually high surface areas (430-720 m2/g), uniform pore sizes (<3.5 nm), and extremely high thermal stabilities (up to 1400 °C) replicated by mesoporous silica hard templates via a one-step nanocasting process. Highly ordered 2-D hexagonal (p6m) and bicontinuous cubic (Ia3d) SiC nanowire arrays have been cast from the hard templates, mesoporous silica SBA-15 and KIT-6, respectively. 

Hollow silicon carbide (SiC) spheres have been synthesized by a microwave heating and carbothermal reduction method with carbon spheres as template and fly ash (a solid waste from coal-fired power plant) as silica source. X-ray diffraction and scanning electron microscope were employed to characterize the morphology, structure of the products. The results show that hollow spheres prepared at 1300 "C under argon atmosphere have a hollow core and SiC shell structure. The shell of a hollow SiC sphere is composed of a lot of irregular SiC nanowires with 5-20 pm in length and 50-500 nm in diameter which belongs to the p-SiC. Moreover, the formation mechanism of the hollow SiC spheres is also discussed. 

G.Z. Shen, D. Chen, K.B. Tang, Y.T. Qian, and S.Y. Zhang, Silicon carbide hollow nanospheres, nanowires and coaxial nanowires, Chem. Phys. Lett., 375,177-184(2003). 

Seong HK, Choi HJ, Lee SK, Lee J, Choi DJ (2004) Optical and electrical transport properties in silicon carbide nanowires. Appl Phys Lett 85 1256... 

Sundaresan SG, Davydov AV, Mark D, Vaudin MD, Levin I, Maslar JE, Tian YL, Rao MV (2007) Growth of silicon carbide nanowires by a microwave heating-assisted physical vapor transport process using group VIII metal catalysts. Chem Mater 19 5531-5537... 

Busiakiewicz, A., Huczko, A., Lange, H., Kowalczyk, P.)., Rogala, M., Kodowski, W., Klusek, Z., Olejniczak, W., Polanski, K., Cudzilo, S. and Datta, P.K. (2008) Silicon carbide nanowires chemical characterization and morphology investigations. Phys. Status Solidi B, 245, 2094-2097. 

Rurali, R. (2005). Electronic and structural properties of silicon carbide nanowires. Physical Review B, 71, 205405. 

Figure 3.5 (a) Transmission electron microscopy (TEM) image of a biphase coaxial silicon nanowire consisting of a crystalline core and an amorphous sheath (b) A biphase silicon carbide nanowire, where the amorphous material has grown predominantly on one side of the nanowire. Silica nanowires can result from the oxidation of silicon/silica nanowires. 

Figure 3.6 Transmission electron microscopy (TEM) images of silicon carbide nanosprings formed from nanowires with circular cross-sections, where the nanospring diameter-to-pitch ratios are (a) 1.8 and (b) 1.23.

---