A Low-cost, Flexible Electrochemical Sensor for Nitrate Detection in Water

This study presents the development and evaluation of a flexible, screen-printed electrochemical sensor for detecting nitrate levels in water. The sensor was composed of a working and a reference electrode. The working electrode was coated with a nanocomposite of poly(3-octyl-thiophene) and molybdenum disulfide and a nitrate-selective layer to improve sensitivity and selectivity. The sensor demonstrated high sensitivity of 9.91 mV/ppm and 8.99 mV/ppm when tested in deionized and lake water, respectively. Additionally, the sensor exhibited excellent repeatability under bending deformations and stability underwater for up to 4 days. Overall, this work offers a scalable and cost-effective solution for continuous monitoring of nitrate levels in direct lake water.