Formaldehyde(CH2O) is a volatile organic compound (VOC) that is widely used in the production of resins, building materials, and household products. It is also a byproduct of combustion and other industrial processes. Exposure to formaldehyde can cause a range of health effects, from mild irritation to serious respiratory issues and cancer. As a result, formaldehyde sensors play a crucial role in ensuring air quality and safety in various environments.

What is a Formaldehyde Sensor?
A formaldehyde sensor is a device designed to detect and measure the concentration of formaldehyde (CH2O or HCHO) in the air. Formaldehyde is a colorless, pungent-smelling gas commonly found in various industrial processes and household products. Due to its potential health hazards, monitoring formaldehyde levels is essential in both residential and industrial environments.

How Formaldehyde Sensors Work
Formaldehyde sensors operate using different principles to detect and quantify the presence of formaldehyde gas. The most common types of formaldehyde sensors include electrochemical sensors, metal-oxide-semiconductor (MOS) sensors, photoionization detectors (PID), and colorimetric sensors.

Electrochemical CH2O Sensors

An electrochemical sensor detects formaldehyde by generating an electrical signal based on chemical reactions occurring within the sensor. It consists of a sensing electrode, a counter electrode, and an electrolyte. When formaldehyde comes into contact with the chemical reagent inside the sensor, a redox (oxidation–reduction) reaction occurs, producing an electric current proportional to the concentration of formaldehyde in the air. This electrical signal is then measured and converted into a concentration value, allowing accurate determination of formaldehyde levels in the environment.