Laboratory Performance Evaluation of a Low-Cost Electrochemical Formaldehyde Sensor

Area of Science:

• Environmental Science
• Analytical Chemistry
• Sensor Technology

Background:

• Formaldehyde is a carcinogenic air pollutant with current detection methods being costly and labor-intensive.
• Emerging low-cost gas sensors offer a potential solution for effective air pollutant monitoring.

Purpose of the Study:

• To evaluate the performance of low-cost electrochemical formaldehyde sensors.
• To assess their suitability for indoor and outdoor air quality monitoring.

Main Methods:

• Laboratory evaluation of eight low-cost electrochemical formaldehyde sensors (SFA30).
• Utilized broadband cavity-enhanced absorption spectroscopy as the reference instrument.
• Investigated the influence of temperature and relative humidity on sensor performance.

Main Results:

• Sensors demonstrated good linearity (R > 0.95), low detection limits (11.3 ± 2.07 ppb), and acceptable accuracy.
• Repeatability was good (3.46% CV), with reasonably fast response times (131-439 s).
• Formaldehyde concentration was the primary factor influencing sensor response, followed by temperature and humidity.

Conclusions:

• Low-cost electrochemical sensors show feasibility for measuring formaldehyde at relevant environmental concentrations.
• These sensors provide a cost-effective alternative for air quality monitoring.
• Further validation in real-world indoor and outdoor settings is suggested.