Out of sintered metal carbides having an extremely high melting point, there is provided a sintered metal carbide which can be produced without having to perform sintering under high pressure such as hot pressing or HIP, having a high relative density and excellent mechanical strength. A sintered metal carbide of at least one metal selected from the group consisting of elements of Groups 4 and 5 of the periodic table, wherein the sintered metal carbide contains Si element of 0.1 wtppm or more and 10,000 wtppm or less.

Out of sintered metal carbides having an extremely high melting point, there is provided a sintered metal carbide which can be produced without having to perform sintering under high pressure such as hot pressing or HIP, having a high relative density and excellent mechanical strength. A sintered metal carbide of at least one metal selected from the group consisting of elements of Groups 4 and 5 of the periodic table, wherein the sintered metal carbide contains Si element of 0.1 wtppm or more and 10,000 wtppm or less.

A method of producing hydrogen gas is provided. The method can include the steps of providing a reaction vessel containing aluminum, delivering a stream of natural gas to the reaction vessel, in which the natural gas includes methane, and heating the reaction vessel at a temperature in a range of 300 to 800? C., in which the heating causes a chemical reaction between the methane and the aluminum to provide hydrogen gas and aluminum carbide. The method can include delivering steam to the reaction vessel and heating the reaction vessel at a temperature in a range of 300 to 800? C., in which the heating causes a chemical reaction between the methane, steam, and the aluminum to provide hydrogen gas, aluminum carbide, and aluminum oxycarbide.

A method of producing hydrogen gas is provided. The method can include the steps of providing a reaction vessel containing aluminum, delivering a stream of natural gas to the reaction vessel, in which the natural gas includes methane, and heating the reaction vessel at a temperature in a range of 300 to 800? C., in which the heating causes a chemical reaction between the methane and the aluminum to provide hydrogen gas and aluminum carbide. The method can include delivering steam to the reaction vessel and heating the reaction vessel at a temperature in a range of 300 to 800? C., in which the heating causes a chemical reaction between the methane, steam, and the aluminum to provide hydrogen gas, aluminum carbide, and aluminum oxycarbide.

Processes for the production of microporous carbon material, for use in electrodes of supercapacitors and secondary batteries, in which particulate metal carbide material is fluidized with a halogen gas at a high temperature in a fluidized bed reactor, the halogen gas is desorbed at a lower temperature of 150? C. to at most 250? C. under vacuum, and then the material is passivated using hydrogen gas and then milled.

An aluminum-diamond composite that exhibits both high thermal conductivity and a coefficient of thermal expansion close to that of semiconductor devices, and that can suppress the occurrence of swelling, etc., of a surface metal layer portion even in actual use under a high load. An aluminum-diamond composite includes 65-80 vol % of a diamond powder having a roundness of at least 0.94, for which a first peak in a volumetric distribution of grain size lies at 5-25 m, and a second peak lies at 55-195 m, and a ratio between the area of the volumetric distribution of grain sizes of 1-35 m and the area of the volumetric distribution of grain sizes of 45-205 m is from 1:9 to 4:6; the balance being composed of a metal containing aluminum.

A method that uses a pressurized reactive medium composed of inert solvents such as pressurized liquid or supercritical fluid carbon dioxide (C02), and sulfur hexafluoride (SF6) and reactive dissolved species ozone (03) and/or boron trifluoride (BF3) and general boron trihalogenides (BX3) to react with two-dimensional (2D) layered materials and thereby synthesize covalently oxygen and/or BX3 functionalized exfoliated 2D layered materials. When 2D layered materials are dispersed in these reactive liquids or fluids by ultrasound sonication or high shear mixing, a simultaneous covalent functionalization and exfoliation of the 2D layered materials happens. Following attainment of the required extent of functionalization and exfoliation, the unreacted 03, BX3, SF6 and C02 can be easily removed as gases by decompression leaving behind the solid phase, thereby leading to efficient and economical production of functionalized and exfoliated 2D layered materials.

The disclosure provides for methods of oxidizing carbide anions, or negative ions, from salt like carbides at low temperatures below about 600 C. In another aspect, the disclosure provides for reactions with intermediate transition metal carbides. In yet another aspect, the disclosure provides for a system of reactions where salt-like carbide anions and intermediate carbide anions are oxidized to produce pure carbon of various allotropes.

The disclosure provides for methods of oxidizing carbide anions, or negative ions, from salt like carbides at low temperatures below about 600 C. In another aspect, the disclosure provides for reactions with intermediate transition metal carbides. In yet another aspect, the disclosure provides for a system of reactions where salt-like carbide anions and intermediate carbide anions are oxidized to produce pure carbon of various allotropes.

The present disclosure provides a negative electrode active material for a fluoride ion battery capable of realizing high charge and discharge capacity, a fluoride ion battery having such a negative electrode active material, and a method for producing such a negative electrode active material for a fluoride ion battery. The negative electrode active material for a fluoride ion battery of the present disclosure has a transition metal carbide having a non-layered structure. The method of the present disclosure for producing a negative electrode active material for a fluoride ion battery comprises applying mechanical impact to a transition metal carbide having a layered structure to convert the transition metal carbide to a transition metal carbide having a non-layered structure.