Low-Power Dissolved Oxygen Sensors for IoT-Based Water Quality Monitoring Networks

How much do we know about dissolved oxygen? Today, let’s introduce relevant knowledge about dissolved oxygen sensors. Measuring dissolved oxygen concentration is required in fields such as medicine, chemistry, environmental monitoring, marine analysis, molecular biotechnology, biological process control, food packaging, and industrial production monitoring. In most cases, continuous monitoring of oxygen concentration becomes the ideal choice, which necessarily relies on dissolved oxygen detection equipment.

Traditional electrochemical methods depend on membrane electrodes and electrolytes, which lead to many problems. Even with regular maintenance, it is still difficult to achieve precise measurements. As a type of optical device, fluorescence-based dissolved oxygen meters can be subdivided into various types according to different application principles, such as absorption spectrometry, reflectometry, luminescence method, infrared spectroscopy, Raman spectroscopy, interferometry, and surface plasmon resonance. In the market, most optical sensors developed for oxygen detection work by leveraging the quenching effect of molecular oxygen on the luminescence of indicator dyes.

Dissolved oxygen sensors are undoubtedly highly efficient detection tools. They determine the concentration of dissolved oxygen by accurately measuring the fluorescence intensity in water. This instrument innovatively adopts the fluorescence method, abandoning traditional membrane electrodes and eliminating the need for frequent replacement of membranes and electrolytes. This significantly reduces maintenance workload and improves work reliability, especially in complex and harsh working conditions such as sewage treatment. Moreover, fluorescence-based sensors do not consume oxygen during operation, so they have no special requirements for water flow rate or agitation level and can effectively avoid interference from substances such as sulfides.