How are the core gas sensors of gas detectors classified
Gas detectors are widely used in industrial construction sites, chemical plants, and places with moderate pollution in daily life. The core part of gas detectors is gas sensors. So, what is the classification of the technical field of gas sensors?
1. Semiconductor gas sensor
Semiconductor gas sensors are widely used in fields such as household gas monitoring, gifts, and smart home appliances.
2. Electrochemical gas sensor
An electrochemical gas sensor is like a name, it tests the concentration of a gas by measuring the current. The advantages of electrochemical gas sensors are their high sensitivity and good selectivity, while the disadvantage is that their service life is usually around two years.
3. Catalytic combustion gas sensor
The combustion gas sensor is not very sensitive to non combustible gases, so its basic application field is to detect combustible gases. Therefore, it is generally used for monitoring combustible gases in petroleum and petrochemical, chemical plants, tobacco companies, and other industries. Its working principle is that gas sensitive materials burn under electricity, and their flammability is affected by the catalyst. The electric heating wire generates temperature due to combustion, thereby changing its resistance value.
4. Optical gas sensor
Photogas sensors mainly include infrared absorption type, spectral absorption type, fluorescence absorption type, etc., mainly including infrared absorption type. Measuring the infrared absorption wavelength can detect gases because different gases have different degrees of absorption of infrared waves. Nowadays, due to its structural connections, the cost is generally quite high.
5. Solid electrolyte gas sensor
Solid electrolyte is a type of chemical battery that uses solid ion conductivity as the electrolyte. It lies between semiconductors and electrochemistry. Selectivity and sensitivity are higher than those of semiconductors, and their lifespan is longer than that of electrochemistry, making them suitable for many applications. The disadvantage is long response time.
