Conducting polymer sensors mechanisms

Sensor technologies are developed using principles of physical and chemical sciences and their interrelationships. Some examples are fiber-optic-based, semiconductor-based, conducting polymer-based, mechanical, electrochemical, calorimetric, and colorimetric sensors. In this section these sensor technologies are discussed with respect to their functions, advantages, capabilities, and requirements. 

Particular cases are potassium selective potentiometric sensors based on cobalt [41] and nickel [38, 42] hexacyanoferrates. As mentioned, these hexacyanoferrates possess quite satisfactory redox activity with sodium as counter-cation [18]. According to the two possible mechanisms of such redox activity (either sodium ions penetrate the lattice or charge compensation occurs due to entrapment of anions) there is no thermodynamic background for selectivity of these sensors. In these cases electroactive films seem to operate as smart materials similar to conductive polymers in electronic noses. 

The references noted well demonstrate the ability to utilize polymer blend technology to achieve the desired balance of mechanical properties and conductivity. The promise of electrical conductive polymers with lower cost, processability, and mechanical durability can thus be envisioned for applications such as electrical dissipative coatings, printable circuits, electromagnetic shielding, resistive heating, conductive sheathing, battery applications, elastomeric conductors, fuses, electronic uses, sensors, specialty electrical devices for corrosive atmospheres, photovoltaic devices, catalysts, optical switches, and semiconductor devices. 

Spectroelectrochemistry is one of the many facets of photoelectroanalytical chemistry. It can be used for numerous purposes in solving the mechanisms of electrochemical processes but especially with electrically conducting polymers it shows its main advantages. The original drive to study conductive polymers arose from the applications anticipated in the energy storage, but these polymers are also interesting from the analytical point of view as potential sensor materials. 

A = electrochromism B = photoelectric conversion C = electrogenerated chemiluminescence D = highly dispersed noble metal E = catalyst F = high mechanical strength conducting polymer, G = charge-controllable transport membrane H = sensor. 

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