Bulk modulus of silicon carbide nanowires and nanosize grains

Study of semiconducting nanomaterials under pressure

“…The pressure induced structural phase transition has been observed experimentally in some semiconducting nanomaterials : ZnO (nanorods), ZnS (2.8, 5, 10 and 25.3 nm), ZnSe (nanoribbons), GaN (2-8 nm), CdSe (4.2 nm), CoO (50 nm), CeO 2 (9-15 nm), SnO 2 (3, 8, 14 nm), SiC (20,30,50, and 130 nm), c-BC 2 N (5-8 nm) and β-Ga 2 O 3 (14.8 ±1.9 nm), using in-situ energy dispersive X-ray diffraction at room temperature [6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22]. The high pressure behavior of two samples of ZnO nanorods with different grain sizes (sample A : diameter 150 nm, length 12000 nm and sample B : diameter 10 nm, length 230 nm) have been studied and compared with their corresponding bulk phase by Xiang et al [6].…”

“…The very useful and demandable semiconducting SnO 2 with different particle sizes transforms from rutile to cubic CaCl 2 structure under pressure [19]. The variation of bulk modulus (B 0 ) of nano SiC has been studied and compared with its corresponding bulk phase under the influence of high pressures for four different sets of nanoparticles [20]. c-BC 2 N has attracted interest of researchers due to its super hardness.…”

Photoluminescence of Surface Modified Silicon Carbide Nanowires

“…Details of the production protocol and precursors used can be found in Refs. [3,7,10] The specimens were heated in air to 500 o C to remove unreacted carbon nanowires and then treated in HF or HNO 3 acids for times varied from 30 minutes to 1 day. At each step we analyzed TEM images, recorded FTIR spectra, x-ray diffraction patterns and photoluminescence spectra.…”

“…[2] Hardness and tensile strength of SiC nanowires are greater than in the case of the larger SiC whiskers. [3,4] Therefore they may be applied as reinforcement to monolithic ceramics in order to improve fracture tolerance and toughness of the composites. [5][6][7] SiC nanowires have already been obtained by various methods, such as the sol-gel process, catalytic chemical vapor deposition, vapor-liquid-solid growth mechanism, reaction between carbon nanotubes (CNT) and SiO vapor at high temperatures, reaction between CNT and liquid or vapor Si, and others [7,8].…”

“…Since 2004, we have produced silicon carbide nanowires from carbon nanotubes and silicon powder in a tube furnace at temperatures between 1100 o C and 1350 o C. [3,7,9,10] We controlled the diameters of nanowires by selecting precursors, and by adjusting the temperature, vapor pressure of silicon, and sintering time. The mechanism of SiC nanowires formation remains controversial, but when metals were present in carbon nanotube precursors, the growth mechanism was identified as the vapor-liquid-solid (VLS) process.…”