Silicon-Carbon Material

Song, J., Jensen, D.S., Hutchison, D.H., Turner, B., Wood, T., Dadson, A., Vail, M.A., Linford, M.R., Vanfleet, R.R., and Davis, R.C. Carbon-nonotube-templated microfabrication of porous silicon-carbon materials with application to chemical separations, Adv. Funct. Mater., 21, 1132-1139, 2011. 

Bands in the region 950-1100 cm"1 have been attributed to the Si=C stretching frequency of the simple silenes, the frequency reported depending on the experimental method, the methodology employed in the calculations, and the substituents present on the ends of the silicon-carbon double bonds there is generally good agreement between these observations and the appropriate calculations. The material has been well summarized.6,153... 

This review describes the current status of silenes (silaethylenes, silaethenes), molecules which contain a silicon-carbon double bond. The heart of the material is derived from a computer-based search of the literature which we believe reports all silenes that have been described to date, either as isolated species, chemically trapped species, proposed intermediates (in reactions where some experimental evidence has been provided), or as the result of molecular orbital calculations. Ionized species... 

Figure 2. Capacity vs. time plot for cell containing carbon-coated silicon powder material. 

Besides silicon, other materials have also been used in micro fuel cells. Cha et al. [79] made micro-FF channels on SU8 sheets—a photosensitive polymer that is flexible, easy to fabricate, thin, and cheaper than silicon wafers. On top of fhe flow channels, for both the anode and cathode, a paste of carbon black and PTFE is deposited in order to form the actual diffusion layers of the fuel cell. Mifrovski, Elliott, and Nuzzo [80] used a gas-permeable elastomer, such as poly(dimethylsiloxane) (PDMS), as a diffusion layer (with platinum electrodes embedded in it) for liquid-electrolyte-based micro-PEM fuel cells. 

In a GPC experiment a mixture of n-alkanes (up to n carbon atoms, where n represents a variable number) and butanol (CH3CH2CH2CH2OH) were injected onto a column maintained at a constant temperature and whose stationary phase was of silicone-type material. The equation of the Kovats straight line derived from the chromatogram is log Jr = 0.39n — 0.29 (where /r the adjusted retention time is in seconds). The adjusted retention time of... 

Silicon—Carbon Thermoset. The Sycar resins of Hercules are silicon—carbon thermosets cured through the hydrosilation of silicon hydride and silicon vinyl groups with a trace amount of platinum catalyst. The material is a fast-cure system (< 15 min at 180°C) and shows low moisture absorption that outperforms conventional thermosets such as polyimides and epoxies. Furthermore, the Sycar material provides excellent mechanical and physical properties used in printed wiring board (PWB) laminates and encapsulants such as flow coatable or glob-top coating of chip-on-board type applications. 

The SiC coating is processed based on the reaction of SiO vapor and carbon materials. Commercial SiO powders (99.9% pure) are provided as the silicon source. The carbon materials are placed on the SiO powder bed via a carbon felt as illustrated in Fig. 10.1. This assembly is covered with carbon sheets in an alumina crucible to keep the SiO gas pressure in the crucible, and heated in a vacuum furnace at various temperatures from 1150 to 1550°C in vacuum (about 0.03 Pa) for periods of time between 1 and 90 minutes. It is necessary to heat at a temperature greater than 1150°C for the vaporization of solid SiO. 

Liu Y, Hanai K, Yang J, Imanishi N, Hirano A, Takeda Y. Silicon/carbon composites as anode materials for Li-ion batteries. Electrochem Solid-State Lett 2004 7 A369-A372. 

Uono H, Kim BC, Fuse T, Ue M, Yamaki JI. Optimized structure of silicon/carbon/graphite composites as an anode material for Li-ion batteries. J Electrochem Soc 2006 153 A1708-A1713. 

Wang CS, Wu GT, Zhang XB, Qi ZF, Li WZ. Lithium insertion in carbon-silicon composite materials produced by mechanical milling. J Electrochem Soc 1998 145 2751-2758. 

The material in this section is organized according to the exchanging groups on silicon carbon for carbon (C/C), carbon for hydrogen (C/H), etc. 

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