Magnesiothermic reduction

As mentioned earlier, magnesiothermic reduction is carried out in a sealed bomb. This steel bomb (400 mm in diameter and 1000-1200 mm in height for about 100 kg of uranium) is provided with a 25 mm MgF2 lining, which is thin enough to permit the influx of... 

The metal beryllium is prepared from its fluoride by magnesiothermic reduction. Calcium can not be used for this purpose because it would interact with beryllium to form a stable intermetallic phase (CaBel3). 

Table 1 summarizes some microstructural and electrochemical properties of porous Si anode materials, as pertaining to the second approach mentioned above, collected from the literature published since 2005. Several synthesis methods have been identified for preparing the porous Si anode materials (column 1, Table 1). One of the two most adopted methods is known as the metal-assisted chemical etching (MACE denoted as E in Table 1). The fundamental principle of this method can be found in the handbook chapter Porous Silicon Formation by Metal Nanoparticle Assisted Etching. Figure 2 shows an example of the MACE-derived porous Si particle. The other most adopted method is magnesiothermic reduction (denoted as M in Table 1). In this method (see handbook chapter Porous Silicon Formation by Porous Silica Reduction ), porous Si oxide materials are reduced by magnesium vapor under high-temperature thermal treatment. The porous Si oxide precursors may be synthesized via the conventional sol-gel processes. Porous Si particles with unique pore structures, such as hollow interior and ordered mesoporosity, may be obtained from Si oxides having the same pore structures which are achieved by using proper templates.

Anodic etching (AE) 2 Coulombic efficiency 5 Electrospraying (ES) 2 Lithium-ion batteries (LIBs) 1 Magnesiothermic reduction 2 Metal-assisted chemical etching (MACE) 2, 4 Solid-electrolyte interphase (SEI) layer 5... 

Table 1 Silicon porosification via magnesiothermic reduction for different applications ...

Hong I et al (2013) Mesoporous Si/C composite anode for Li battery obtained by magnesium-thermal reduction process. Solid State Ionics 232 24-28 Huachao T et al (2013) Preparation of porous Si/C anode materials by magnesiothermic reduction method. J Chin Ceram Soc 41(8) 1046-1050... 

Jia H et al (2011) Novel three dimensional mesoporous silicon for high power lithium ion battery anode material. Adv Energy Mater 1(6) 1036-1039 Jiang Z et al (2013) Facile fabrication of three dimensional Si/SiC composites via one step magnesiothermic reduction at relative low temperature. Mater Res Bull 48 4139-4145 Jung DS et al (2013) Recycling rice husks for high capacity lithium battery anodes. Proc Natl Acad SciUS A 110 12229-12234... 

Ma B et al (2013) Preparation of porous silicon by magnesiothermic reduction from serpentine. Key Eng Mater 544 29-33... 

Magnesiothermic fabrication 2 Magnesiothermic reduction 4 Magnesium vapor 2 Porous silica reduction 4 Porous silicon formation 4 Reduction chemistries 1 Silica feedstocks 2 Sodium 4... 

Magnesiothermic reduction of silica Conversion reaction Mesoporous Microporous Bao et al. (2007) 2007... 

Chen W, Fan ZL, Dhanabalan A, Chen CH, Wang CL (2011) Mesoporous silicon anodes prepared by magnesiothermic reduction for lithium ion batteries. J Electrochem Soc 158 A1055-A1059. doi 10.1149/ 1.3611433... 

Industrial production of B4C is based on fusion of boric oxide and carbon in electric furnaces operated around 2500 C. This process leads to lumps of coarse-grained material of high purity which has to be milled for sinter powders. Finer powders are obtained by magnesiothermic reduction of the boric oxide at lower temperatures around 1750°C ... 

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