Bornitrid is extensively used in nanoelectronics, photonics, cosmetics, and ceramics. Its hardness is almost equal to diamond. Boron nitride is very strong, having low density, which makes it lightweight and high strength material. It is well known for its use in engineering ceramics.
What Is Boron Nitride?
Bornitrid is an inorganic compound. Its crystal is composed of boron and nitrogen, having a chemical formula of BN. It has a special crystal structure which is analog of graphite. Its strong chemical and thermal properties are mainly due to its crystal structure in which boron is covalently bonded with nitrogen. Boron nitride is synthesized in the laboratories because of its scarcity in nature. Boron nitride can be classified in many different forms.
Each form or shape of boron nitride has its own distinguished properties and applications. Main types, their structure and applications are given in the table:
Synthesis of Boron Nitride
Since BN does not exist in quantities that can be used in nature, all commercial boron nitride must carefully synthesize boron nitride. Preparation of boron nitride depends on what shape you want:
Production of Hexagonal Boron Nitride (h-BN)
Hexagonales Bornitrid (h-BN) is produced using physical or chemical assembly processes. The most common method is to mix boric acid (H₃BO₃) or boron oxide (B₂O₃) with ammonia (NH₃) or urea. This reaction occurs at a very high temperature of 800-1200 ° C:
B₂O₃ + 2NH₃ → 2BN + 3H₂O
This process usually occurs in a nitrogen atmosphere. This reaction produces a hexagonal white boron nitride powder that can be pressed and used in various applications while it is hot.
A little interesting, manufacturers often need to add something like calcium phosphate in this process. Boron compounds melt at quite low temperatures, so they flow together before reacting properly.
Production of cubic boron nitride (c-BN)
The synthesis of boron nitride (c-BN) requires higher pressure and higher temperature. The process usually starts with h-BN boron nitride powder and then follows:
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Add catalysts (usually alkaline metal or alkaline soil metal).
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Use of very high pressure (5 GPa, about 50,000 times the normal pressure)
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Heat from about 1500 to 2000.
Under such extreme conditions, the six-way crystal structure changes to a cubic crystal. Like graphite becomes diamond.
New Manufacturing Methods
New methods of producing boron nitride include:
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Chemical vapor phase growth method (CVD) especially suitable for the production of thin films and boron nitride coatings.
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Pressurized steam/condenser method for more pure results
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Epitaxy method for special electronic boron nitride applications
Each method has its own unique advantages in controlling purity, crystal size, and boron nitride structure.
Properties That Make Boron Nitride Special
Boron nitride has unique properties that make it increasingly popular in various industries. Let’s look at the characteristics of boron nitride:
Hexagonales Bornitrid (h-BN)
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Appearance: White and slippery boron nitride powder (feel like talc)
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Structure: layered hexagonal pattern (like graphite, alternating B and N atoms)
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Dichte: Boron nitride is a dense compound having density of about 2.1 g/cm³.
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Thermal conductivity of boron nitride: Convey heat well along the surface (up to W/m·K)
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Boron nitride electrical insulation: Excellent insulator with wide band gap (~ 5.9 ev).
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Lubricity: low friction, especially at high temperatures
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Chemical resistance: not reacting with most acids and molten metals
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Thermische Stabilität: Up to 1000 ° C in air and up to 2800 ° C in inert gas
I have always wondered. The h-BN structure has very high thermal conductivity but provides excellent boron nitride electrical insulation.
Cubic Boron Nitride (c-BN)
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Appearance Amber to black crystals
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Looks like a diamond at the structural atomic level
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The density of boron nitride is about 3.48 g/cm³, which is significantly higher than h-BN.
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Hardness Extremely hard (Mohshärte ~ 9.5)
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Boron nitride thermal conductivity: convey heat well in all directions (~ W/m·K)
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Chemical stability Higher temperature than diamond
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Oxidation resistance: oxidation resistance up to 1300 ° C
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Electrical properties Dope for making semiconductors is possible
c-BN does not react with materials containing iron at high temperatures, but diamonds react. Therefore, c-BN can help you to cut steel.
To understand the properties better let’s have a comparison of the different form in the table below:
Examples of Actual Use
You may be surprised that there are many industries that use boron nitride. Here is where boron nitride is used:
Manufacturing And Metalworking
Boron nitride cubic crystals can help industries achieve better results in the following applications:
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Cutting tools for quenched steel
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Strong grinding stone for metal
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High precision machining that does not work well with diamonds
The shape of h-BN is also useful:
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High temperature lubricant in metal molding
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Mold Relief in Casting
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Crucible for metal melting
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Boron nitride coating for protection against wear and corrosion
In Electronics and Thermal Management
Both forms of boron nitride can help your electronics cool and operate normally:
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Materials between high temperature components and heat sinks utilizing the high thermal conductivity of boron nitride
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Electronic device surface
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Insulation layer of capacitor using excellent electrical insulation of boron nitride
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Material to diffuse the heat of LED lighting
Boron hexagonal nitride works particularly well as a base for graphene and other two-dimensional electronic materials, such as flat atomic scales.
In Cosmetics (Surprising, Right?)
Surprisingly, boron nitride can help cosmetic products achieve better performance. The h-BN form is widely used in makeup because it:
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Creates a smooth, silky feel
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Helps products spread evenly
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Absorbs oil from the skin
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Makes fine lines less noticeable
Next time when you pick up some foundation, eyeshadow, or face powder, check the ingredients you might spot boron nitride in cosmetics.
In Aerospace and High-Temperature Applications
Boron nitride’s ability to handle extreme temperatures can help aerospace application in:
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Systems that protect spacecraft from heat
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Parts in rocket engines
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Insulation that works at high temperatures
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Components in gas turbines
In Research Fields
Scientists are finding new boron nitride uses in:
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Bornitrid nanotubes (like carbon nanotubes but more stable)
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Thin-film devices für quantum computing
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Medical implants that are compatible with the body
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New kinds of batteries and energy storage
Future Directions
Ongoing boron nitride research can help industries develop new applications in:
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2D Materials: Ultra-thin h-BN sheets for next generation electronics
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Boron Nitride Nanotubes: BN versions of carbon nanotubes with superior heat processing
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Quantum Applications: Using h-BN to protect quantum materials
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Biomedical Applications: Drug delivery and medical imaging Exploring the potential of BN in
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Energy storage: advanced battery and capacitor components
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Advanced boron nitride coating technology to enhance material protection.
Production cost remains a challenge, especially with kubisches Bornitrid. However, research continues on more efficient boron nitride synthesis methods, which may make this wonderful material more accessible.
Abschluss
Due to its unique combination of properties, Bornitrid can help solve challenges across numerous industries, from cutting tools to cosmetics. As manufacturing improves, this amazing material will find its way into even more products.
Want to learn more about advanced materials? Check out our other articles on ceramics and their industrial applications.