A Model of Polyelectrolyte Conductance in Moist Solvents as a Basis of Water Sensors

Abstract

The conductance of interpenetrated polymer networks (IPNs) containing quaternary amino groups was studied in cyclohexane, toluene, ethyl ether, ethyl acetate, and tetrahydrofurane as a function of water content by electrochemical impedance spectroscopy. IPNs were then used as sensitive materials to detect water traces in organic solvents with promising results for the construction of a moisture sensor. The detection onset for water concentration increased with the dielectric constant of the solvent. Different IPN-based sensors in the same solvent showed a detection limit at lower water concentration if their characteristic plot [conductance/relative humidity (RH%) in air] was shifted toward lower RH%. This suggests that the composition of this class of polymers can be tuned to achieve the best performance for each solvent.

Role of nanostructured polymers on the improvement of electrical response-based relative humidity sensors

“…Works on humidity sensing mechanism of most widely used impedance type sensors have been carried out using dielectric impedance spectroscopy [63,64,65,66,67,68].…”

Efficient Reversible Optical Sensing of Water Achieved through the Conversion of H‐Aggregates of a Merocyanine Salt to J‐Aggregates

“…Therefore, there is a need to develop, faster, and easy to use portable water sensing systems with optical signals. The sensors with the optical response and high sensitivity are well suited for this purpose in comparison to electrochemical or electrophysical methods using electrodes or other means, as they are simple and convenient to use under laboratory and industrial conditions ,. Although, colorimetric and fluorimetric sensors are reported dealing with the detection of water ,.…”

Fluorescence Quenching of a Europium Coordination Compound for the Detection of Trace Amounts of Water: Uncovering the Response Mechanism by Structural Confirmation

“…Different methods have been applied to measure the amount of water on the basis of electrical or optical signal changes. The most commonly used materials and equipment are electrodes,1 polymers,2 multilayer films,3 and luminescent sensors 4–6. Molecular materials based on europium coordination compounds are of particular interests as fluorescent probes owing to their high luminous efficiencies and narrow spectral widths 7–9…”