Auburn University Develops Paper-Based Temperature and Moisture Sensors

In the Journal of Laser Applications, by AIP Publishing, researchers at Auburn University in Alabama introduced their paper-based temperature and humidity sensors that are accurate and reliable, as well as eco-friendly. The sensors can help measure factors that are critical to crop-plant growth. The research team created temperature and humidity sensors by printing silver lines on four types of commercially available paper through a process called dry additive nanomanufacturing. Changes in the ability to store electrical energy, called capacitance, and resistivity in the printed electrodes are monitored to determine shifts in temperature and humidity. As the paper absorbs water vapor, its capacitance change is measured to reflect the relative humidity of the environment. The sensors proved reliable and sensitive to changes in temperature and humidity levels. They successfully detected changes in relative humidity levels from 20% to 90% and temperature variations from 25 C to 50 C. Additionally, the biodegradable sensors are affordable and can be reused, and when the time comes, they can be disposed of safely. “In recent years, agriculture has been hit heavily by drastic changes in environmental factors such as humidity and temperature, thereby driving the urgency for innovative solutions to enhance productivity and improve quality with minimal environmental impact,” said author Masoud Mahjouri-Samani.