What types of gas sensors are available?
Время публикации: 2019-12-20 10:34:59
Gas sensor classification
A gas sensor is a sensor that converts gas components and concentrations into electrical signals. In the production and life of modern society, various gases are exposed and need to be tested and controlled. Such as the detection and control of gas components in chemical production, the detection and alarm of coal mine gas concentration, the monitoring of environmental pollution, gas leakage, fire alarm, detection and control of combustion conditions.
There are many types of gas sensors, including gas sensors for sensitive gas types, vacuum gas sensors for sensitive gas volumes, and gas component sensors for detecting gas components. The former mainly includes a semiconductor gas sensor and a solid electrolyte gas sensor, and the latter mainly has a high frequency component sensor and an optical component sensor. Semiconductor gas sensors have a wide range of applications due to their high sensitivity, fast response, long life and low cost.
How does a semiconductor gas sensor work?
A semiconductor gas sensor uses a semiconductor gas sensor to contact a gas to cause a change in semiconductor properties to detect a component of a specific gas or to measure its concentration.
Semiconductor gas sensors are generally classified into two types, resistive and non-resistive. Resistive semiconductor gas sensors use gas-sensitive semiconductor materials such as tin oxide (SnQ2), manganese oxide (MnO2) and other metal oxides to make sensitive components when they absorb fumes such as hydrogen, carbon monoxide and alkanes. In the case of ether, drunk, benzene, natural gas, etc., a reduction reaction occurs, and heat is released to increase the temperature of the element and the resistance changes. Using this characteristic of the semiconductor material, the composition and concentration of the gas are converted into electrical signals for monitoring and alarming.
The components are sensitive to different gases, such as diethyl ether, ethyl alcohol, hydrogen, etc., and have low sensitivity to methane. Generally, as the concentration of the gas increases, the resistance of the element increases significantly, and within a certain range, it has a linear relationship.
Gas sensor material
The material of the gas resistance resistor is a metal oxide semiconductor (sub-P type such as tin oxide and N type such as cobalt oxide), and the synthetic material sometimes penetrates into a catalyst such as palladium (Pd), platinum (Pt), silver (Ag) or the like.
The gas sensor is mainly used for the monitoring, forecasting and automatic control of flammable, explosive, toxic and harmful gases in the natural gas, gas, petrochemical and other sectors of the industry. The gas sensor is chemically sensitive with the composition of the chemical substance as the detection parameter. element.Тег: gas sensors