The present invention relates to a method for producing a fibre-reinforced, transparent composite material (10), comprising the following steps: a) providing a material matrix melt and b) producing reinforcing fibres (14), step b) of the method comprising the steps of b1) providing a mixture having a silicon source and a carbon source, the silicon source and the carbon source being present together in particles of a granulated solid; b2) treating the mixture provided in step a) of the method at a temperature in a range from 1400 C. to 2000 C., more particularly in a range from 1650 C. to 1850 C.; thereby producing reinforcing fibres (14), the method comprising the further steps of c) introducing the reinforcing fibres (14) into the material melt; and d) optionally cooling the material melt to form a transparent composite material (10). A method of this kind allows a composite material to be produced that is able to unite high transparency with outstanding reinforcing qualities.

The present invention relates to a silicon anode active material capable of high capacity and high output, and a method for fabricating the same. A silicon anode active material according to an embodiment of the present invention includes a silicon core including silicon particles; and a double clamping layer having a silicon carbide layer on the silicon core and a silicon oxide layer between the silicon core and the silicon carbide layer.

A silicon carbide wafer and a method of fabricating the same are provided. In the silicon carbide wafer, a ratio (V:N) of a vanadium concentration to a nitrogen concentration is in a range of 2:1 to 10:1, and a portion of the silicon carbide wafer having a resistivity greater than 10.sup.12 .Math.cm accounts for more than 85% of an entire wafer area of the silicon carbide wafer.

A method of recycling silicon wastewater includes forming a silicon slurry from the silicon wastewater using a micro filtration device, forming a silicone cake from the silicon slurry using a filter press, and forming a silicon powder by drying the silicone cake in a reducing atmospheric.

A method of recycling silicon wastewater includes forming a silicon slurry from the silicon wastewater using a micro filtration device, forming a silicone cake from the silicon slurry using a filter press, and forming a silicon powder by drying the silicone cake in a reducing atmospheric.

A silicon carbide crystal ingot includes first crystal layers and second crystal layers, each being alternately disposed and all containing one of a donor and acceptor, wherein a concentration of the donor or the acceptor that at least one of the second crystal layers has is higher than a concentration of the donor or the acceptor that one of the first crystal layers has, the one of the first crystal layers being in contact with the at least one of the second crystal layers.

A process for producing reaction bonded silicon carbide (RBSC) from high purity, porous, essentially all-carbon preforms through contacting said preforms with silicon metal at room temperature, and subsequently heating to melt silicon metal and cause infiltration into said preform causing reaction to silicon carbide and leaving residual silicon, to result in a dense silicon carbide-silicon composite. The process offers the ability to produce RBSC with higher purity, higher strength, and lower cost as long as the carbonaceous preforms are of sufficient purity and pore size distribution to allow for uniform, crack-free bulk bodies to be fabricated.

The invention relates to a nano silicon-carbon composite negative material for lithium ion batteries and a preparation method thereof. A porous electrode composed of silica and carbon is taken as a raw material, and a nano silicon-carbon composite material of carbon-loaded nano silicon is formed by a molten salt electrolysis method in a manner of silica in-situ electrochemical reduction. Silicon and carbon of the material are connected by nano silicon carbide, and are metallurgical-grade combination, so that the electrochemical cycle stability of the nano silicon-carbon composite material is improved. The preparation method of the nano silicon-carbon composite material provided by the invention comprises the following steps: compounding a porous block composed of carbon and silica powder with a conductive cathode collector as a cathode; using graphite or an inert anode as an anode, and putting the cathode and anode into CaCl.sub.2 electrolyte or mixed salt melt electrolyte containing CaCl.sub.2 to form an electrolytic cell; applying voltage between the cathode and the anode; controlling the electrolytic voltage, the electrolytic current density and the electrolytic quantity, so that silica in the porous block is deoxidized into nano silicon by electrolytic reduction, and the nano silicon-carbon composite material for lithium ion batteries is prepared at the cathode.

Inside a furnace body with a vacuum environment or under the inert gas protection, the raw silicon material used to produce silicon carbide is melted or vaporized in a high temperature environment over 1300 C., and then the melted or vaporized raw silicon material will react with the carbonaceous gas or liquid to form silicon carbide. The present invention uses the carbonaceous gas with no metallic impurities, to replace petroleum coke, resin, asphalt, graphite, carbon fiber, coal, charcoal and some other carbon sources used in current production processes. When the carburizing reaction is in progress, the raw silicon material is melted or vaporized and the reaction takes place in the air. No container is required, so impurity contamination is lessened, and the produced silicon carbide has a fairly high purity.

The present disclosure relates to porous silicon dioxide-carbon composites and a method for preparing high-purity -phase silicon carbide granular powders using the same. More particularly, it relates to a method for preparing high-purity -phase silicon carbide granular powders in accordance with a first step of preparing gel wherein carbon compounds are uniformly dispersed in silicon dioxide network structures generated by a sol-gel process using a silicon compound and a carbon compound in a liquid state as raw materials, a second step of preparing porous silicon dioxide-carbon composites, in which the carbon compounds are solidified, dried and then thermally treated to have a high specific area, and a third step of conducting both of a direct reaction between carbon and metallic silicon and a carbothermal reduction between carbon and silicon dioxide through a two-step treatment process of the prepared porous silicon dioxide-carbon composites powders with the added metallic silicon, wherein the average particle size, particle size distribution and purity of the silicon carbide powder can be adjusted by controlling a heating rate, a heat treatment temperature and time during the heat treatment process.