Gas sensor

As-Salaam-Alaikum, Welcome to my blogger "World of Knowledge".Here we discuss the topic Gas Sensors.

Points to be discuss in this Article are given below:

• Gas Sensor
• Difference between gas sensor & human nose
• Application of gas sensor
• How gas sensor works

Gas sensor:

A gas sensor is a device which detects the presence or concentration of gases in the atmosphere. Based on the concentration of the gas the sensor produces a corresponding potential difference by changing the resistance of the material inside the sensor, which can be measured as output voltage. Based on this voltage value the type and concentration of the gas can be estimated.

Difference between gas sensor & human nose:

Gas Sensor a device that detects certain gas particles on the sensor surface reaction occurs with a specific nano material sending information to the program Alerts the device with the detected gas

Human Nose a body part that smells and intakes the air reaction occurs in olfactory epithelium sending information to the brain Alerts the brain with the detected smell

Applications of Gas Sensors:

• Animal Farming
• Environmental Monitoring
• Industrial Process
• Food Industry
• Aeronautic and Space
• Homeland Security
• Medical Dignostics

Homeland Security:

Homeland Security Now: 

Bomb sniffing sensor - Currently bomb detection at the airports and ports is done by very inexpensive yet quite highly accurate 'dogs' and very expensive and time/energy consuming methods of sample collecting and analyzing.

Homeland Security Future:

The goal in developing nanotechnology enabled sensors is to achieve reliable, extremely sensitive and inexpensive sensors that can be mass produced and deployed in large enough numbers so that the cost of detection by law enforcement will be less than the cost of deployment by terrorists.

One example of a next-generation nanotechnology explosives detector is a nanocomposite film that shows very fast fluorescence response to trace vapors of explosives such as TNT, DNT or NB.

Agricultural Industry:

Each year, billions of dollars worth of fruit and vegetable are wasted during shipping and storage because of premature ripening and rotting of the goods. The cause it ethylene; signature compounds of the ripening process are ethanol, acetaldehyde, and various esters.  Trace analysis of these compounds is required.

Aeronautic and Space:

Hydrogen, hydrocarbon, nitrogen oxides, carbon monoxide, oxygen, and carbon dioxide sensors being developed to be used in aerospace for  leak, fire, and emission sensor applications.

E-Nose:

Gas sensors being developed and researched using nanomaterials can be applied in many fields behaving like a human or a dog nose that has high sensitivity to numerous smells. A sensor so small with high sensitivity, high stability and low cost will be an optimal goal. However, many factors such as temperature and humidity are still in the way of perfecting the optimal sensor.

How Gas Sensor works:

In the sensor, the gas diffuses into the sensor, through the back of the porous membrane to the working electrode where it is oxidized or reduced. This electrochemical reaction results in an electric current that passes through the external circuit.