Polypyrrole free‐standing electrodes sense temperature or current during reaction

Abstract

The electrochemical activity of self-supported thick (70 µm) polypyrrole films electrogenerated in a mixed electrolyte of dodecylbenzenesulfonic acid and LiClO 4 was studied in aqueous solutions of LiClO 4 . This material inhibits hydrogen evolution up to cathodic potentials of −3.0 V versus Ag/AgCl. During oxidation or reduction reactions under galvanostatic conditions, the electrical energy consumed for a constant charge is a function of either the working temperature or the flowing current. As a consequence any electrochemical device, moreover artificial muscles, constructed with reactive conducting polymers is expected to work simultaneously as a sensor of the working temperature.

Structural Electrochemistry from Freestanding Polypyrrole Films: Full Hydrogen Inhibition from Aqueous Solutions

“…[ 5 ] Other self-supported CPs, like polypyrrole/DBSA [ 49 ] or PEDOT, [ 50 ] also present a broad voltammetric potential window in different solutions.…”

Biomimetic Conducting Polymers: Synthesis, Materials, Properties, Functions, and Devices

“…42 12.1.1 Dual Sensing-Actuators: Sensing and Tactile Artificial Muscles. Equation (17) states that the evolution of the muscle potential during actuation is affected, as obtained empirically 26,108,121,122,124,[129][130][131][132][133] by the electrolyte concentration, the temperature, any mechanical variable acting on the volume variation (trailed weights, obstacles, pressure) and frequency. Driven by a constant current, the potential of the muscle (and the consumed electrical energy) during the description of the same angular amplitude every time, that is, from Figs.…”

Conducting polymer actuators: from basic concepts to proprioceptive systems

“…Under flow of a constant current (constant reaction rate) the achieved potential evolution is lower when a variable favouring the electrochemical reaction increases. This is the case for temperature [96,[98][99][100][101] or electrolyte concentration [96][97][98][99]225]. On the other hand, the potential evolution shifts to higher values for rising values of those variables retarding the reaction rate (it needs more energy to happen): the muscle moves higher masses [99] or moving faster the same mass by applying now rising currents [98,100,184].…”

“…This fact can be used for the development of new multi-functional devices where two, or more tools, work simultaneously by exploiting the simultaneous change of two or more composition dependent properties. Some preliminary empirical results have been advanced in this field as dual sensor-actuators: artificial muscles sensing chemical working conditions [96][97][98][99][100], muscles sensing thermal conditions [96,98,100,101], muscles sensing mechanical conditions as trailed masses [96,97] or the presence of obstacles giving tactile muscles [102]; Vidal et al have reported the development of dual electrochromic (UV-vis or IR) artificial muscles [103].…”

“…The most important empirical results related to this thesis is that the muscle potential evolution and the consumed electrical energy evolution during bilayer or trilayer muscles actuation sense, while moving, the influence of the same physical and chemical variables, giving sensing and tactile artificial muscles. The dual actuating-sensing property is observed from artificial muscles constituted by both families of conducting polymers: exchanging anions or cations [96,98,99,101,102]. Using the experimental setup shown in figure 5 the muscle potential response is recorded while a current is applied to the artificial muscle, producing a mechanical work.…”