A Brief Discussion on the Specific Classification of Electrochemical Gas Detectors
In certain special environments, the surrounding air may contain toxic, flammable, and other gases. If people enter such an environment, it is very dangerous. Therefore, if we want to know the types of gases in the air within a spatial range, gas detectors can come in handy. At present, there are many types of gas detectors in the market, among which electrochemical gas detectors are one of the commonly used gas detectors. Now, let's learn about the specific classification of electrochemical gas detectors.
1, Original battery type gas sensor
Also known as: Gaffney battery type gas sensor, also known as fuel cell type gas sensor, also known as spontaneous cell type gas sensor, their principle is the same as the dry cell we use, except that the carbon manganese electrode of the battery is replaced by a gas electrode. Taking an oxygen sensor as an example, oxygen is reduced at the cathode, and electrons flow through an ammeter to the anode, where lead metal is oxidized. The magnitude of the current is directly related to the concentration of oxygen. This type of sensor can effectively detect oxygen, sulfur dioxide, chlorine gas, etc.
2, Constant potential electrolytic cell gas sensor
This type of sensor is very effective for detecting reducing gases. Its principle is different from that of the original battery type sensor. Its electrochemical reaction occurs under the force of current, and it is a true Coulomb analysis sensor. This type of sensor has been successfully used in the detection of gases such as carbon monoxide, hydrogen sulfide, hydrogen, ammonia, hydrazine, etc. It is currently the mainstream sensor for detecting toxic and harmful gases.
3, Concentration battery gas sensor
The gas with electrochemical activity spontaneously forms a concentration electromotive force on both sides of the electrochemical cell, and the magnitude of the electromotive force is related to the concentration of the gas. Successful examples of such sensors are oxygen sensors for automobiles and solid electrolyte carbon dioxide sensors.
4, Extreme current gas sensor
There is a sensor for measuring oxygen concentration that uses the principle that the maximum current in the electrochemical cell is related to the carrier concentration to prepare an oxygen (gas) concentration sensor, which is used for oxygen detection in automobiles and oxygen concentration detection in molten steel.
The above content is the specific classification of electrochemical gas detectors. A considerable portion of flammable, toxic and harmful gases in electrochemical gas detectors have electrochemical activity and can be electrochemically oxidized or reduced. By utilizing these reactions, gas composition can be distinguished and gas concentration can be detected.
