The present invention discloses a selenium-doped MXene composite nano-material and a preparation method thereof, comprising the following steps: (1) adding MXene and an organic selenium source into a dispersant, and stirring to prepare a dispersion with a concentration of 1 mg/ml to 100 mg/ml; (2) transferring the dispersion into a reaction kettle, then heating, reacting, and then naturally cooling to a room temperature; (3) washing the product obtained in the step (2) with a cleaning agent, then centrifuging to collect a precipitate, and drying the precipitate under vacuum; and (4) placing the sample obtained in the step (3) into a tubular furnace for calcination, introducing protective gas, heating, and then cooling to a room temperature to obtain the selenium-doped MXene composite nano-material. The material prepared by the present invention has high specific surface area, good electrical conductivity, cycle stability performance, rate performance and high theoretical specific capacity.

The present invention discloses a selenium-doped MXene composite nano-material and a preparation method thereof, comprising the following steps: (1) adding MXene and an organic selenium source into a dispersant, and stirring to prepare a dispersion with a concentration of 1 mg/ml to 100 mg/ml; (2) transferring the dispersion into a reaction kettle, then heating, reacting, and then naturally cooling to a room temperature; (3) washing the product obtained in the step (2) with a cleaning agent, then centrifuging to collect a precipitate, and drying the precipitate under vacuum; and (4) placing the sample obtained in the step (3) into a tubular furnace for calcination, introducing protective gas, heating, and then cooling to a room temperature to obtain the selenium-doped MXene composite nano-material. The material prepared by the present invention has high specific surface area, good electrical conductivity, cycle stability performance, rate performance and high theoretical specific capacity.

The present invention relates to novel tungsten carbide powder which a specific BET-surface, crystallite number and size, to a method for the production and use thereof.

The present invention relates to novel tungsten carbide powder which a specific BET-surface, crystallite number and size, to a method for the production and use thereof.

The present invention(s) is directed to novel conductive M.sub.n+1X.sub.n(T.sub.s) compositions exhibiting high volumetric capacitances, and methods of making the same. The present invention(s) is also directed to novel conductive M.sub.n+1X.sub.n(T.sub.s) compositions, methods of preparing transparent conductors using these materials, and products derived from these methods.

The present invention(s) is directed to novel conductive M.sub.n+1X.sub.n(T.sub.s) compositions exhibiting high volumetric capacitances, and methods of making the same. The present invention(s) is also directed to novel conductive M.sub.n+1X.sub.n(T.sub.s) compositions, methods of preparing transparent conductors using these materials, and products derived from these methods.

A surface-coated cutting tool includes a substrate and a coating film that coats the substrate, wherein the coating film includes a WC.sub.1-x layer composed of a compound represented by WC.sub.1-x, where x is more than or equal to 0.54 and less than or equal to 0.58, the compound represented by WC.sub.1-x includes a hexagonal crystal structure, and a maximum point of a peak exists in a range of 31.2 to 31.4 eV in a spectrum diagram of a 4f orbital of a tungsten element obtained when measuring the WC.sub.1-x layer by an X-ray photoelectron spectroscopy analysis method.

A surface-coated cutting tool includes a substrate and a coating film that coats the substrate, wherein the coating film includes a WC.sub.1-x layer composed of a compound represented by WC.sub.1-x, where x is more than or equal to 0.54 and less than or equal to 0.58, the compound represented by WC.sub.1-x includes a hexagonal crystal structure, and a maximum point of a peak exists in a range of 31.2 to 31.4 eV in a spectrum diagram of a 4f orbital of a tungsten element obtained when measuring the WC.sub.1-x layer by an X-ray photoelectron spectroscopy analysis method.

The present invention provides an amorphous tungstic acid fusion formed by agglomerating primary particles of tungstic acid, wherein the amorphous tungstic acid fusion has a grape-bunch-shaped structure formed therein as the primary particles of tungstic acid are interconnected. According to one embodiment of the present invention, eco-friendly and low-cost process technology can be provided that attains a reduction in process cost and a significant decrease in air and water pollutant emissions by not proceeding with an ATP process.

The present invention provides an amorphous tungstic acid fusion formed by agglomerating primary particles of tungstic acid, wherein the amorphous tungstic acid fusion has a grape-bunch-shaped structure formed therein as the primary particles of tungstic acid are interconnected. According to one embodiment of the present invention, eco-friendly and low-cost process technology can be provided that attains a reduction in process cost and a significant decrease in air and water pollutant emissions by not proceeding with an ATP process.