Exactly What Is Going Down With AMN-107 — различия между версиями
(Новая страница: «Therefore, it can be concluded that the yield of SiC nanowires was about 53%. The inset in Fig.?4a displays the corresponding EDX spectrum, indicating three eleme…»)
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Therefore, it can be concluded that the yield of SiC nanowires was about 53%. The inset in Fig.?4a displays the corresponding EDX spectrum, indicating three elements (silicon, carbon, and oxide) exist in the nanowires. The TEM image in Fig.?4c shows detailed structure of the nanowire. One can find that the nanowire has a core-shell nanocabled structure. According to the component ratio obtained by EDX results, the core ought to be crystallized SiC and the shell is amorphous SiO2. In fact, the unique core-shell SiC/SiO2 structure has also been observed by other researchers [18�C20]. Fig.?4 a The SEM image of SiC nanowires; b the magnified SEM image of SiC nanowires; and c the TEM image of SiC nanwires with a core-shell SiC/SiO2 structure. AMN-107 The inset in a shows the EDX pattern of SiC nanowires Vapor�Cliquid�Csolid LGK-974 (VLS) mechanism has usually been used to explain the growth process of 1D nanomaterials . However, it seems unsuitable to interpret our experiments and results because there is no catalyst liquid droplet available during the high-frequency induction heating procedure. The oxide-assisted cluster-solid mechanism proposed by Zhang et?al. , which was established to interpret the growth process of Si/SiO2 nanowires, may be used to understand the growth process of core-shell SiC/SiO2 nanowires. In terms of this mechanism, there exist three processes, that is, nucleation, precipitation, and growth. Figure?5 illustrates the schematic diagram of growing process. As the temperature is up to 1,600?��C, SiO powder will vaporize and react with the carbon source as follows: Fig.?5 Schematic diagram of growing process of SiC nanowire $$ 3 \textSiO\left( \textv \right) + 3 \textC\left( \texts \right) = 2 \textSiC\left( \texts IAP inhibitor \right) + \textSiO_ 2 \left( \texts \right) + \textCO\left( \textv \right)$$ (1)where v and s refer to vapor and solid states of the material, respectively. It will generate SiC and SiO2 nanoparticles in this process, which provide crystalline nucleus for growth of nanowires. Actually, three different atoms (silicon, carbon, and oxygen) contained in the nanoparticles. The superfluous of any element will lead to the occurrence of precipitation (separate out) process. Reaction?2 can occur under a supersaturated condition of CO : $$ \textSiO \left( \textv \right) + 3 \textCO \left( \textv \right) = \textSiC \left( \texts \right) + 2 \textCO_ 2 \,(\textv). $$ (2) When SiO vapor is prevail, the following reaction will occur: $$ 3 \textSiO \left( \textv \right) + \textCO \left( \textv \right) = \textSiC \left( \texts \right) + 2 \textSiO_ 2 \,(\texts). $$ (3) No matter what reaction is in the ascendant, SiC can generate and provide to the nanoparticles.