Solar grade silicon

Solar-grade silicon, production of, 22 507-508 Solar heat control, use of gold in, 12 703 Solarization effect, 19 203 Solar photocatalysis, 23 23-24 Solar photocatalytic detoxification, 19 76 Solar photocatalytic processes, 19 100-101 Solar photocatalytic reactor, using deposited titania, 19 99 Solar photoreactors, 19 95-99 Solar salt harvesting, 22 802, 806-808 Solar spectrum, 23 2 Solar still, 26 89-92 Solar thermal converters, 23 10-13 Solar transmittance, for thin films, 23 19 Solatene, 24 558 Solder, 3 53... 

Presently, the availability of solar-grade silicon is limited, and its cost is over 30/kg and rising. The largest supplier of polycrystalline silicon (Hemlock Semiconductor Corp.) is building new production facilities, and users such as Sharp Corporation and BP Solar are working on designing thinner panels requiring less silicon. 

Besides the traditional markets for carbon, some novel applications for the carbon produced via methane decomposition are discussed in the literature. Kvaemer has initiated R D program to investigate the potential of novel grades of carbon black as a storage medium for hydrogen, and as a feedstock for the production of solar grade silicone.35 The production of carbon nanotubes and nanofibers via solar thermal decomposition of methane over supported Co and Ni catalysts, respectively, was also reported.36... 

POSTER TITLE Thermodynamic and Experimental Study on P Removal from Si-based Alloy for Solar Grade Silicon Refining... 

Ceccaroli, B. Lohne, O. Solar grade silicon feedstock. In Handbook of Photovoltaic Science and Engineering Luque, A., Hegedus, S., Eds. Wiley Chichester, 2003 153-204. 

Trace-Element Characterization of Silicon. In order to define "solar grade" silicon with sufficient precision to make the optimum economic choice among possible production processes, Davis et al. doped a series of silicon ingots with single transition metal impurities and produced curves relating normalized photovoltaic efficiency to the concentration of the contaminant (36). Establishing the x-axis of these curves was not entirely straightforward. As a contribution to this work, NBS measured concentrations of a number of dopants in these samples, with the detection limits found in Table I. An illustration of the difficulty faced in this work is that forty percent of the concentrations determined at NBS differed from the nominal concentration by a factor of two or more. 

Photovoltaics also require significant research activity in the chemical sciences. Low-cost methods are required for producing solar-grade silicon for photovoltaic cells. Better solar cell materials are needed than the presently utilized amorphous silicon. These materials must be more efficient without the use of heavy metals such as cadmium, tellurium, indium, and lead, which present significant environmental issues. An understanding of the degradation process of photovoltaic cells is needed, as is an answer to why these materials lose their effectiveness after prolonged exposure to the sun. Finally, there is a need to develop catalysts for the efficient photochemical conversion of water. 

Buldini, P.L., Mevoh, A., Lai Sharma, J. (1998) LA-ICP-MS, IC and DPASV-DPCSV determination of metallic impurities in solar-grade silicon. Talanta, 47,203-212. 

Lasne, C., Gazet-Talvande, J., Barraud, J. (1984) Chapter 6. Spark source mass spectrometry analysis— Its application to polycrystalline solar grade silicon. Progress in Crystal Growth and Characterization, 8,151-165. 

For industrial use, silicon can be classified into three categories according to their purity metallurgical grade silicon (MG-Si, 2N), solar grade silicon (SOG-Si, 6N-7N), and semiconductor grade silicon (SEG-Si, 11N-12N). Currently MG-Si is produced by carbothermic reduction of sihca. The world production of MG-Si, excluding ferrosihcon, was ca. 1.5 million metric ton in 2011 [1]. S(Xj-Si is mainly produced from MG-Si by Siemens process which involves the... 

Qishi T, Watanabe M, Koyama K, Tanaka M, Saegusa K (2011) Process for solar grade silicon production by molten salt electrolysis using aluminum-silicon liquid alloy. J Electrochem Soc 158 E93-E99... 

Zou XY, Xie HW, Zhai YC, Lang XC, Zhang J (2011) Electrolysis process for preparation of solar grade silicon. Adv Mater Res 391-392 697-702... 

The PV industry has been very good at reducing costs however, it is going to run up against a barrier in the cost of the silicon feedstock used to make solar cells. Low-cost, low-energy technologies must be developed that can take the raw material (quartz) and refine it into solar-grade silicon. 

Yasuda, K., et al., Improving Pmity and Process Volume During Direct Electrolytic Reduction of Solid Si02 in Molten CaC12 for the Production of Solar-Grade Silicon. Energy Technol. (Weinheim, Ger.), 2013. 7 p. 245-252. 

Oishi, T., et al.. Process for Solar Grade Silicon Production by Molten Salt Electrolysis Using Aluminum-Silicon Liquid Alloy. J. Electrochem. Soc., 2011.158 p. E93-E99. 

Morvan D, Amouroux J and Claraz P (1984) Analysis of electronic and solar grade silicon by atomic emission spectroscopy from inductively coupled plasma. Progress in Crystal Growth and Characterization 8 175 180. 

Bessho, M Fukunaka, Y Kusuda, H and Nishiyama, T, (2009) High-grade silica refined from diatomaceous earth for solar-grade silicon production. Energy Fuels, 23, 4160-4165,... 

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