Due to the increase in environmental pollution, there has also been a similar increase in demand for gas sensors.
While there are many materials to make one, Silicon Carbide is the most promising and most durable gas sensor material.
Why is this and what are its benefits?
Let’s find out.
What Is Silicon Carbide
Advanced ceramic materials come in all shapes and forms, each with its unique characteristics.
However, very few of them have high chemical stability, mechanical strength, heat resistance, or high sensitivity for gas molecules.
This is where Silicon Carbide comes in, and not just that, these are what makes it stand out.
Silicon Carbide has all these qualities and many other important properties needed for very high performing gas sensors.
While Silicon Carbide is an advanced ceramic material, it has more durable qualities, thus making it suitable for industrial usage.
What Are Gas Sensors?
Basically, gas sensors are used to identify different types of gas.
They’re used to detect and identify gas emissions that we may not necessarily be able to see with the eyes.
However, its practical usage is to detect toxic gasses, and also to measure gas concentration.
They are often used in industry to detect gas leaks and also for nonindustrial usage, especially as environmental pollution increases.
Great gas sensors consist materials that are chemically durable and that are good semiconductors.
And these are all the qualities of Silicon Carbide.
Properties Of Silicon Carbide
While Silicon Carbide is also an advanced ceramic material, it has unique qualities that make it different from the others.
From its high mechanical strength, semi-conductor activities, excellent chemical stability, and to several other qualities.
Silicon carbide usage and similarly Silicon carbide application in gas sensors is mainly because of these outstanding qualities.
Let’s check them out:
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Wear Resistance
Silicon carbides are tough and are highly wear resistant, they can easily resist scratches or any other surface damages.
Even when they are exposed to continuous gas flows, they still maintain this unique quality.
Silicon carbide application in gas sensors, leads to long term performance, even with contaminations and constant airflow.
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Strength
You might have heard that diamond is hard, but do you know what’s as hard as diamond, its Silicon Carbide.
Silicon Carbide is among the hardest advanced ceramic materials that exists.
Silicon Carbide measures about 9.2 on the Mohs scale, and that’s just a little below diamond.
This gives it the ability to easily with physical strains and rough environments.
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Chemical Stability
Unlike other advanced ceramic materials, Silicon Carbide has an impressive chemical stability level.
It doesn’t react or falter under harsh chemical conditions like some other advanced ceramic materials do.
It is very resistant to acids and other corrosive gasses.
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Excellent Thermal Conductivity
Another quality of Silicon carbide is the ability to quickly dissipate heat.
This can help avoid cases of overheating.
And you what this means for gas sensors?
Silicon Carbide application in gas sensors means sensors can stay cooler and stable even in fluctuating environments.
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Wide BandGap
Silicon Carbide has a perfect bandgap which allows it to easily detect changes in electrical properties.
This also makes it a very excellent quality for gas sensor usage.
Silicon Carbide application in gas sensors, especially with this characteristic makes a sensor to easily detect gas concentration.
What Are Gas Sensors Made Of?
We´ve earlier explained that gas sensors are used to detect different types of gas and also to detect gas emissions.
Now we are going to discuss its components.
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Sensing Materials
One of the most important components of gas sensors is called Sensing material.
This is what helps gas sensors to detect and quantify targeted gasses.
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Substrate
Again, there is the Substrate, this supports the sensing materials earlier discussed, it makes sure they function appropriately.
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Heater Element
Now this is the last and one of the most important properties.
What this does is that it warms up the sensing materials.
For gas sensors, a warmer is needed to warm up the sensing material.
These three components make gas sensors effectively detect and identify different types of gas.
Is Silicon Carbide An Advanced Ceramic Material?
Yes, Silicon Carbide is an advanced ceramic material.
It has several properties peculiar to advanced ceramic materials, and even much more that are not.
This is what makes it stand out.
These peculiar advanced materials characteristics include and isn’t limited to high mechanical strength, high thermal conductivity, and so many others.
How Are Gas Sensors Made?
The manufacturing process of gas sensors involves many processes, let’s take a cursory glance at them:
The first thing to do is to select appropriate substrate that can perform well under harsh temperature
Silicon Carbide comes into play here, as it is often chosen for its high durability.
The next thing is to deposit sensing materials on the selected Silicon Carbide substrate that has been chosen.
After this, metals are then deposited onto the sensing materials, this is aimed at creating electrodes.
Lastly, a heater is added in some gas sensors to better foster the temperature of the sensing materials inside.
The Manufacturing Process Of Silicon Carbide
There are many methods and processes for producing Silicon Carbide.
We have the Acheson Process, the Lely process, and as well as the Chemical Vapor infiltration.
Let’s take them one after the other:
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Lely Method
While using this method, Silicon Carbide is put inside a graphite container.
Then it is set to heat at 2,500°C in an inert gas atmosphere.
With the heating, the Silicon Carbide dissipates and is poured into cooler surface where it forms an high quality crystal.
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Acheson Method
Here Silica and carbon like materials like coke are mixed and then heated at very high temperature.
This process of heating causes a chemical reaction that produces Silicon Carbide.
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Chemical Vapor Infiltration Method
Using this method, a gas that has properties of Silicon is brought into a space with materials like carbon fibers.
When the temperature is elevated, the gas deposits Silicon Carbide onto the fibers.
Each of these methods is chosen and used based on the Silicon Carbide usage that is intended.
Differences Between Silicon Carbide And Other Advanced Ceramic Materials
Silicon Carbide is unique as compared to other advanced ceramic materials, due to two reasons:
1. Because it has typical properties of advanced ceramic materials.
2. Because it also has unique characteristics that make it more suitable for gas sensors.
Also, Silicon Carbide has high thermal conductivity, this makes it easy for gas sensors to detect gas.
The chemical stability of Silicon Carbide also makes gas sensors prevent false and wrong readings
This durability and chemical stability make Silicon Carbide surpass other advanced ceramic materials.
This makes it a very suitable material for gas sensors.
The Application Of Silicon Carbide
Due to the durability and many other qualities of Silicon Carbide, gas sensors made from it are used in various field.
Let us check them out.
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Aerospace
Here, Silicon Carbide helps to detect and alert when there is a case of a fuel leak.
With its characteristics like sensing materials, it can measure emissions in aircraft and so doing, help reduce societal pollution.
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The automotive industry
Silicon Carbide acts as a watch to limit and control excess gas exhaustions from automobiles.
This also helps contribute to the fight against environmental pollution.
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And also, in industrial processes
In manufacturing industries and other big power plants, Silicon carbides are used to detect when gas leaks.
This helps to prevent hazards.
What Are The Importance Of Silicon Carbide In Gas Sensors
Silicon Carbide is a very important material in glass sensors.
With its unique components, it stands out as one of the most appropriate materials for various gas sensor applications.
Why?
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Excellent Resistance To temperature
Unlike other advanced ceramic materials, Silicon Carbide can perform even excellently under extreme temperatures.
For gas sensor applications in places like car engines, this chemical stability feature of Silicon Carbide can bolster its effectiveness.
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Strength
Thanks to the strength and durability of Silicon Carbide, gas sensors made from it last longer than those that aren’t.
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Chemical Stability
Silicon Carbide doesn’t falter under harsh chemical conditions like some other advanced ceramic materials do.
This makes gas sensors to perform well, even under harsh chemical conditions.
In Conclusion
Silicon Carbide isn’t just any usual advanced ceramic material.
It has all the typical components of an advanced ceramic materials and many more.
Its uniqueness makes it a very great material for gas sensors.
With this, its relevance in gas sensors and other industrial usage isn’t going to diminish.