Real-Time Nitrate Ion Monitoring with Poly(3,4-ethylenedioxythiophene) (PEDOT) Materials

Abstract

Nitrate (NO3) pollution in groundwater, caused by various factors both natural and synthetic, contributes to the decline of human health and well-being. Current techniques used for nitrate detection include spectroscopic, electrochemical, chromatography, and capillary electrophoresis. It is highly desired to develop a simple cost-effective alternative to these complex methods for nitrate detection. Therefore, a real-time poly (3,4-ethylenedioxythiophene) (PEDOT)-based sensor for nitrate ion detection via electrical property change is introduced in this study. Vapor phase polymerization (VPP) is used to create a polymer thin film. Variations in specific parameters during the process are tested and compared to develop new insights into PEDOT sensitivity towards nitrate ions. Through this study, the optimal fabrication parameters that produce a sensor with the highest sensitivity toward nitrate ions are determined. With the optimized parameters, the electrical resistance response of the sensor to 1000 ppm nitrate solution is 41.79%. Furthermore, the sensors can detect nitrate ranging from 1 ppm to 1000 ppm. The proposed sensor demonstrates excellent potential to detect the overabundance of nitrate ions in aqueous solutions in real time.

Recent Advances in Conductive Polymers-Based Electrochemical Sensors for Biomedical and Environmental Applications

“…In the VPP process, monomer gases undergo a series of chemical reactions in the gas phase to form a polymer film or coating [ 143 ]. By employing VPP technology, Kohler’s group prepared a real-time sensor based on PEDOT for the detection of nitrate ions through monitoring changes in electrical properties [ 144 ]. The sensitivity of the sensor to nitrates is influenced by various polymerization parameters such as temperature, pressure, and time.…”

Comparison of the analytical performance of two different electrochemical sensors based on a composite of gold nanorods with carbon nanomaterials and PEDOT:PSS for the sensitive detection of nitrite in processed meat products

“…The negative charge of nitrite may be adsorbed on the surface of the modied GCE due to electrostatic interactions with positively charged PEDOT chains or with the positive charge on the surface of the AuNRs. 76 In addition, interactions may also occur between ErGO and nitrite molecules via hydrogen bonding on the surface of the modied electrode. This condition facilitates nitrite accumulation at the interface of the electrode/electrolyte, which favors the electron transfer process to enhance the electrocatalytic properties of the material composite.…”