Unlock instant, AI-driven research and patent intelligence for your innovation.

A high-pressure preparation method of pure-phase molybdenum dinitride

A high-voltage, silicon nitride technology, applied in chemical instruments and methods, nitrogen compounds, nitrogen-metal/silicon/boron binary compounds, etc., can solve problems such as difficult to obtain high-purity products, and achieve good industrial application prospects, The effect is simple and easy to implement

Active Publication Date: 2019-08-13
INST OF FLUID PHYSICS CHINA ACAD OF ENG PHYSICS
View PDF3 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, this method is also difficult to obtain high-purity products when the incubation time is as long as 20 hours

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • A high-pressure preparation method of pure-phase molybdenum dinitride
  • A high-pressure preparation method of pure-phase molybdenum dinitride
  • A high-pressure preparation method of pure-phase molybdenum dinitride

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0025] Mix anhydrous sodium molybdate with analytically pure boron nitride (with a particle size of 2 microns) at a molar ratio of 1.0:2.0, press the powder into a cylindrical molding and place it in a high-pressure assembly of pyrophyllite. The assembly uses graphite tubes as heating parts and sodium chloride as pressure transmission medium. The synthetic pressure is 2.0GPa, the temperature is 500°C, and the holding time is 30 minutes. After the heating is stopped, the molded product is naturally cooled to room temperature, the pressure is relieved, the molded product is ground into a powder and then ultrasonically cleaned in 70°C hot water for 30 minutes. After centrifugation, the washing-centrifuging operation was repeated 3 times, and the obtained solid powder was dried in a drying oven at 60°C for 3 hours. MoN thus obtained 2 The XRD and SEM are as figure 1 with figure 2 As shown in (a), it can be seen from the figure that the main phase of the product is MoN 2 , Its morp...

Embodiment 2

[0027] Anhydrous sodium molybdate and analytically pure boron nitride (particle size 2 microns) are mixed with a molar ratio of 1.5:2.0, and the powder is pressed into a cylindrical shape and placed in the pyrophyllite high-pressure assembly. The assembly uses graphite tubes as heating parts and sodium chloride as pressure transmission medium. The synthetic pressure is 2.0GPa, the temperature is 500°C, and the holding time is 30 minutes. After the heating is stopped, the molded product is naturally cooled to room temperature, the pressure is relieved, the molded product is ground into a powder and then ultrasonically cleaned in 70°C hot water for 30 minutes. After centrifugation, the washing-centrifuging operation was repeated 3 times, and the obtained solid powder was dried in a drying oven at 60°C for 3 hours. MoN thus obtained 2 The XRD and SEM are as figure 1 with figure 2 As shown in (b), it can be seen from the figure that the MoN synthesized under this condition 2 It i...

Embodiment 3

[0029] Anhydrous sodium molybdate is mixed with analytically pure nano-silicon nitride at a molar ratio of 6.0:1.0, and the powder is pressed into a cylindrical molding and placed in a high-pressure assembly of pyrophyllite. The assembly uses graphite tubes as heating parts and sodium chloride as pressure transmission medium. The synthetic pressure is 2.0GPa, the temperature is 500°C, and the holding time is 30 minutes. After the heating is stopped, the molded product is naturally cooled to room temperature, the pressure is relieved, the molded product is ground into a powder and then ultrasonically cleaned in 70°C hot water for 30 minutes. After centrifugation, the washing-centrifuging operation was repeated 3 times, and the obtained solid powder was dried in a drying oven at 60°C for 3 hours. MoN thus obtained 2 XRD image 3 As shown in the figure, the main phase of the product is SiO 2 And MoN 2 Mixed phase.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention relates to a high-pressure preparation method of pure-phase molybdenum dinitride. The method is characterized by successively comprising the following steps: (1) taking sodium molybdate,boron nitride or silicon nitride as raw materials, weighing and grinding in proportion, mixing uniformly and then pressing to form a molded product; (2) putting the molded product into a high-pressure assembly, wherein the high-pressure assembly is arranged in a high-pressure press machine for pressurizing and heating, keeping pressure at 1-5GPa, keeping temperature at 400-600 DEG C and keeping heat preservation time for 15-30min, after completing temperature preservation, cooling, relieving pressure and taking out the molded product; (3) washing the molded product obtained in step (2) for 10-60min by using hot distilled water at 40-80 DEG C after grinding, and then centrifuging a solid matter; and (4) placing the solid matter obtained in step (3) into a drying box at 40-80 DEG C to dry for 2-6h to obtain molybdenum dinitride powder; wherein the sodium molybdate and the boron nitride are ground and mixed in a molar ratio of (1.1 to 3.0) to 2.0, and the sodium molybdate and the siliconnitride are ground and mixed in a molar ratio of (2.0 to 2.5) to 1.0. The high-pressure preparation method has the advantages that the method is simple and easy to implement, can be used for quicklypreparing the pure-phase molybdenum dinitride in batches, and thus has a very good industrial application prospect.

Description

Technical field [0001] The invention belongs to the field of preparation of transition metal nitride powder materials, and is specifically a high-pressure preparation of pure phase molybdenum dinitride. Background technique [0002] Transition metal nitrides have received extensive attention in the past ten years due to their excellent catalytic properties (hydrotreating, light and electrochemical catalysis, etc.). In particular, they also have excellent resistance to sulfur poisoning and can be used as a substitute for precious metals in the field of catalysis. Molybdenum nitrides have catalytic properties similar to those of platinum group metals in some reactions such as dehydrogenation and hydrogenolysis. [0003] MoN 2 Is a new type of layered structure compound, which is compatible with MoS 2 It has a similar layered structure, and its catalytic activity for the hydrodesulfurization of thiofluorene is MoS 2 It also has very good catalytic activity for the synthesis of methan...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(China)
IPC IPC(8): C01B21/06
CPCC01B21/062C01P2002/72C01P2004/03
Inventor 李绪海刘利新徐亮王媛操秀霞孟川民王志刚
Owner INST OF FLUID PHYSICS CHINA ACAD OF ENG PHYSICS