What is Lithium Nitride and its Preparation?

Lithium nitride, a metal nitrogen compound with the chemical formula Li3N, is a purple or red crystalline solid with a pale green luster in reflected light and a ruby color in transmitted light. Long-term exposure to air will eventually turn into lithium carbonate. Alkaline metal nitride chemistry is extremely limited, and of the binary compounds only lithium nitride is stable and easy to prepare (sodium and potassium nitrides can only be prepared under more extreme conditions).

Lithium nitride preparation

Lithium nitride can be prepared by directly reacting elemental nitrogen and lithium, usually by burning lithium in pure nitrogen. Whether in the laboratory or in industry, this method is the best way to prepare lithium nitride. Commonly used methods. In addition, nitrogen gas can also be passed into liquid sodium in which metal lithium is dissolved, and the lithium nitride prepared by the latter has a higher purity.

method one

The method is to directly react metal lithium and pure nitrogen at high temperature, and the purity of the obtained product can reach 95% to 99%.

Preparation device:

1—nitrogen bottle; 2—cooling pipe; 3—electric furnace; 4—rubber stopper;

G-reaction tube; J-U-shaped tube; K-backflow bottle;

L—washing bottle; M—glass cock

The nitrogen gas was passed through a U-shaped tube filled with phosphorus pentoxide and a quartz tube with red hot copper chips to fully deoxidize. Nitrogen was then passed through a potassium hydroxide drying tube and a scrubber of concentrated sulfuric acid to further remove moisture. The reaction tube is an iron tube with a length of 90 cm and an inner diameter of 5 cm, and a small iron plate and a large iron plate are installed in the tube. There is a resistance wire outside the tube for heating and a thermocouple to measure the temperature.

First, pass nitrogen through the reaction tube (Note: Preparing the reaction, running the reaction, and finishing the reaction are always under nitrogen). Gradually increase the temperature to 200°C in order to drive out the air and moisture in the reaction tube. After the reaction tube was cooled, a freshly cut 0.5cm lithium particle was added to the small plate for deoxygenation and dehydration. Add 10 to 12 lithium grains of the same size to the large plate as a reactant. After aeration for 1 h, the temperature was slowly raised to 450 °C. After the reaction, slowly open the cock and gradually reduce the nitrogen pressure. After the reaction tube was cooled to room temperature, the lithium nitride product was taken out.

Method Two

In the method, a zirconia crucible is used as a container, and the reaction is carried out at a high temperature of 800° C. to obtain lithium nitride crystals.

Preparation device:

a—zirconia crucible; b—iron crucible; c—porcelain tube; d—reaction instrument

a is a zirconia crucible coated with a layer of molten lithium fluoride (melting point 840°C), put a in an iron protective crucible b, and then put both into a high temperature resistant porcelain tube c. The porcelain tube was capped with a glass lid and sealed. The glass cover is connected with the three-way piston, which can be vacuumized or gas can be introduced. There is a serpentine tube around the sealing part of the glass cover and the porcelain tube, which can pass cooling water.

Scrape the surface of lithium in an operation box vented with argon gas, cut it into small pieces, and put it into crucible a under the protection of argon gas. After the porcelain tube is sealed, vacuum is drawn, nitrogen is passed through, and the operation is repeated several times. If you want to make a larger lithium nitride crystal, you can start nitriding at 400 ° C, and dilute pure and dry nitrogen with 20% (volume fraction) of high-purity argon, and then gradually heat up to 800 ° C to obtain nitrogen Lithium.

Overview of lithium nitride Li3N powder

Lithium nitride is a metal nitrogen compound with the molecular formula Li3N. It is the only stable alkali metal nitride. It is a violet or red crystalline solid with a high melting point, light green in reflected light and ruby in transmitted light. Prolonged exposure to air will eventually produce lithium carbonate. The chemical properties of basic metal nitrides are extremely limited. Among binary compounds, only lithium nitride is stable and easy to prepare (sodium nitrite and potassium nitride can only be prepared under more extreme conditions).

Lithium nitride belongs to the hexagonal crystal system. In a lithium nitride crystal, there is a layer of lithium and nitrogen consisting of lithium and nitrogen atoms. Lithium atoms are arranged in graphite crystals like carbon atoms, and nitrogen atoms are located in the center of the hexagon of lithium atoms. There is a lithium layer between the lithium layer and the nitrogen layer. Since the ratio of lithium and nitrogen in the lithium layer and the nitrogen layer is 2:1, that is, Li2N (which does not conform to the stoichiometric formula Li3N), so every two layers between the lithium layer and the nitrogen layer. In the unit cell of lithium nitride, the distance between Li-N is 213 pm, which is close to the sum of the ionic radii of lithium ions and nitrogen anions. The distance between each lithium nitrogen layer and the adjacent lithium layer is 194pm,

At room temperature, metal lithium can partially form lithium nitride when exposed to air, and lithium in nitrogen flow forms lithium nitride, which is 10 to 15 times faster than lithium in air, and then all lithium becomes lithium nitride. In contrast, other alkali metals have difficulty forming nitrides. For example, sodium nitrite can only be prepared by depositing an atomic beam on sapphire at low temperature and decomposing it with slight heating. Lithium nitride is easily hydrolyzed to form lithium hydroxide and ammonia, especially fine powdered lithium nitride, which will burn violently when heated in air. Therefore, lithium nitride must be handled in an inert atmosphere such as nitrogen. It is used as a nitriding agent in organic reactions and as a reducing agent and nitrogen source in inorganic reactions.

Lithium nitride has been discovered since the late 19th century and is easily prepared by combining elements. Research on the reaction of lithium nitride with hydrogen began in the early 20th century. Daft and Miklauz found that lithium nitride reacts with hydrogen gas at 220-250°C to form a substance composed of "Li3NH4". They went on to heat the material at a higher temperature (>>; 700°C) to produce "Li3NH2" and hydrogen gas.

Lithium Nitride Li3N Powder Application

Lithium nitride is prepared by the direct reaction of elemental nitrogen and lithium, usually by burning lithium in pure nitrogen. In the laboratory and industry, this method is the most commonly used method for preparing lithium nitride. Alternatively, nitrogen gas can be injected into liquid sodium dissolved in lithium metal to produce purer lithium nitride. Lithium nitride has many applications.

1. Solid electrolyte

Lithium nitride is a fast ionic conductor with higher electrical conductivity than other inorganic lithium salts. Many studies have been conducted on the use of lithium nitride as a solid electrode and cathode material for batteries.

2. Fast ionic conductors

A series of lithium fast ion conductors have been prepared based on lithium nitride. As a fast ionic conductor material, it should have higher decomposition voltage, lower electronic conductivity, higher ionic conductivity and better chemical stability.

3. Preparation of Boron Nitride from Lithium Nitride

Lithium nitride (Lin3) is a catalyst for the synthesis of (boron nitride) CBN at high temperature and pressure. Lithium nitride catalyzes the conversion of Bn to CBN and the reaction of B4C and NH4A at atmospheric pressure and high temperature. It can also be used as a nitrogen source for solvothermal reaction with Bbr3 to generate Bn and CBn. Besides being used as a solid electrolyte, lithium nitride is also an efficient catalyst for converting hexagonal boron nitride to cubic boron nitride.

4. Using lithium nitride to prepare lithium difluorosulfinate salt.

Lithium sulfoxide (LIN(SO2F)2, hereinafter referred to as LIFSI) is a promising electrolyte. LiFSI has suitable electrical conductivity, high thermal and electrochemical stability

5. Preparation of cubic boron nitride from lithium nitride

Preparation of lithium boron nitride (Li3BN2). Li3BN2 is an important catalyst for the synthesis of cubic boron nitride superhard materials, and has been used in the industrial production of cubic boron nitride synthesis. The hardness of cubic boron nitride is lower than that of diamond, but diamond cannot be used to grind ferrous metals, so cubic boron nitride is currently the best grinding material for ferrous metals and their alloys.

Lithium Nitride Li3N Powder Price

The price of lithium nitride Li3N powder will vary randomly with the production cost, transportation cost, international situation, exchange rate and market supply and demand of lithium nitride Li3N powder. Tanki New Materials Co., Ltd. aims to help industries and chemical wholesalers find high-quality, low-cost nanomaterials and chemicals by providing a full range of customized services. If you are looking for lithium nitride Li3N powder, please feel free to send an inquiry for the latest price of lithium nitride Li3N powder..

Lithium Nitride Li3N Powder Supplier

As a global lithium nitride Li3N powder supplier, Tanki New Materials Co., Ltd. has extensive experience in the performance, application and cost-effective manufacturing of advanced and engineered materials. The company has successfully developed a series of powder materials (including oxides, carbides, nitrides, single metals, etc.), high-purity targets, functional ceramics and structural devices, and provides OEM services.

Technical Data of Lithium Nitride Li3N Powder