A redox-generated biomimetic membrane potential across polypyrrole films

2019 ◽  
Vol 55 (67) ◽  
pp. 10023-10026
Author(s):  
Xiaoyan Nie ◽  
Tianliang Xiao ◽  
Zhaoyue Liu
Keyword(s):  
Membrane Potential ◽  
Artificial Membrane ◽  
Polypyrrole Films ◽  
Polypyrrole Film ◽  
Biomimetic Membrane ◽  
Anion Distribution ◽  
Two Sides

An artificial membrane potential was generated through redox-regulating anion distribution on the two sides of a polypyrrole film.

Study on Morphologies of Palladium Coated Foam Nickel Cathodes for Dechlorination of 2,4-Dichlorophenol

2012 ◽  
Vol 571 ◽  
pp. 97-101 ◽  
Author(s):  
Jun Jing Li ◽  
Hui Ling Liu ◽  
Zhi Wei Wang ◽  
Xiu Wen Cheng
Keyword(s):  
Electron Microscopy ◽  
Aqueous Solution ◽  
Composite Electrode ◽  
Potential Temperature ◽  
Nickel Electrode ◽  
Polymerization Time ◽  
Applied Potential ◽  
Polypyrrole Films ◽  
Polypyrrole Film ◽  
Scanning Electron

Electrolytically deposited palladium on polypyrrole film, which is electropolymerized using potentiostatic method, covered foam nickel electrode as a support was used as cathode for the electrocatalytic hydrodechlorination of 2, 4-dichlorophenol in aqueous solution. It is well known that the morphologies of polypyrrole films have dramatic influences on the dispersion of metals and the performance of the composite electrode. The influence of applied potential, temperature and polymerization time on the morphology of the films was studied by scanning electron microscopy (SEM). The fundamental electrocatalytic hydrodechlorination (ECH) results indicated that the electrocatalytic activity of Pd loaded polypyrrole foam nickel electrode is excellent for dechlorination of 2,4-dichlorophenol. The present study shows a promising choice of this kind of composite electrode for ECH.

Corrosion Resistance of Nd-Fe-B Magnets Coated with Polypyrrole Films

2006 ◽  
Vol 530-531 ◽  
pp. 111-116
Author(s):  
M.C.E. Bandeira ◽  
F.D. Prochnow ◽  
Isolda Costa ◽  
César V. Franco
Keyword(s):  
Corrosion Resistance ◽  
Electrochemical Impedance ◽  
Nacl Solution ◽  
Corrosion Performance ◽  
Low Frequencies ◽  
Polypyrrole Films ◽  
Phosphate Ions ◽  
Polypyrrole Film ◽  
Corrosive Environments ◽  
Magnet Surface

Nd-Fe-B magnets present outstanding magnetic properties. However, due to their low corrosion resistance, their applications are limited to non-corrosive environments. Nowadays, significant efforts are underway to increase the corrosion resistance of these materials, through the use of coatings. Herein are presented the results of a study on the corrosion resistance of Nd-Fe-B magnets coated with polypyrrole (PPY). The electrochemical behavior of coated and uncoated magnets has been studied by Electrochemical Impedance spectroscopy (EIS) in synthetic saliva. The results were compared to previous investigations, which were carried out under similar conditions, in Na2SO4 and NaCl solutions. In sulphate solution, the corrosion resistance of the PPY-coated magnet was 3 times larger (1600 .cm2) than that of uncoated magnet (500 .cm2). In NaCl solution, however, the corrosion resistance of coated and uncoated magnets were very similar (250 .cm2). In synthetic saliva, both the uncoated and coated magnets presented good corrosion performance (1940 .cm2). Such behavior can be attributed to the phosphate ions in saliva, which play a role as corrosion inhibitor, producing phosphating, at least partially, of the magnet surface. The PPY-coated magnets presented a strong diffusional control from moderate to low frequencies, caused by the polypyrrole film. The thicker PPY film increased the corrosion resistance of the magnet in synthetic saliva.

Actuative Properties of CP Actuator Consisting of Polypyrrole Film and Solid Polymer Electrolyte

2007 ◽  
Vol 336-338 ◽  
pp. 341-344 ◽  
Author(s):  
Hye Ran Kang ◽  
Hae Do Jung ◽  
Jang Oo Lee ◽  
Nam Ju Jo
Keyword(s):  
Polymer Electrolyte ◽  
Conducting Polymer ◽  
Electrolyte Solution ◽  
Solid Polymer Electrolyte ◽  
Oxidation Process ◽  
Electrochemical Polymerization ◽  
Solid Polymer ◽  
Polypyrrole Films ◽  
Polypyrrole Film

Conducting polymer (CP) actuators undergo volumetric changes due to the movement of dopant ions into the film during the electrical oxidation process. However, it may be an impediment for practical use of polypyrrole actuator that polypyrrole usually requires electrolyte solution for actuation. To solve this problem, solid polymer electrolyte(SPE) was introduced in CP actuator instead of electrolyte solution. And PPy/SPE/PPy electroactive tri-layer actuator was prepared by the electrochemical polymerization of pyrrole and the actuation characteristics were studied. An all-solid actuator, consisting of two polypyrrole films and a solid polymer electrolyte based on polyurethane, clearly showed a reversible displacement in an atmosphere when a voltage was applied.

Lipid Transmembrane Asymmetry and Intrinsic Membrane Potential:  Two Sides of the Same Coin

2007 ◽  
Vol 129 (17) ◽  
pp. 5358-5359 ◽  
Author(s):  
Andrey A. Gurtovenko ◽  
Ilpo Vattulainen
Keyword(s):  
Membrane Potential ◽  
Two Sides

scholarly journals Whole-ganglion imaging of voltage in the medicinal leech using a double-sided microscope

2017 ◽  
Author(s):  
Yusuke Tomina ◽  
Daniel A. Wagenaar
Keyword(s):  
Membrane Potential ◽  
Sensory Processing ◽  
Action Potentials ◽  
Large Population ◽  
Medicinal Leech ◽  
Simultaneous Recording ◽  
Neuronal Dynamics ◽  
Using Data ◽  
Almost All ◽  
Two Sides

AbstractStudies of neuronal network emergence during sensory processing and motor control are greatly promoted by technologies that allow us to simultaneously record the membrane potential dynamics of a large population of neurons in single cell resolution. To achieve whole-brain recording with the ability to detect both small synaptic potentials and action potentials, we developed a voltage-sensitive dye (VSD) imaging technique based on a double-sided microscope that can image two sides of a nervous system simultaneously. We applied this system to the segmental ganglia of the medicinal leech. Double-sided VSD imaging enabled simultaneous recording of membrane potential events from almost all of the identifiable neurons. Using data obtained from double-sided VSD imaging we analyzed neuronal dynamics in both sensory processing and generation of behavior and constructed functional maps for identification of neurons contributing to these processes.

scholarly journals The Influence of Carbon Nanotubes on the Protective Properties of Polypyrrole Formed at Copper

Materials ◽  
2019 ◽  
Vol 12 (16) ◽  
pp. 2587
Author(s):  
Ursula Carragher ◽  
David Branagan ◽  
Carmel B. Breslin
Keyword(s):  
Carbon Nanotubes ◽  
Corrosion Protection ◽  
Polymer Films ◽  
Charged Surface ◽  
Protective Properties ◽  
Polypyrrole Films ◽  
Dodecylbenzene Sulfonate ◽  
Polypyrrole Film ◽  
Anionic Micelles

Protective polypyrrole films doped with dodecylbenzene sulfonate (DBS) were formed at copper, while carbon nanotubes (CNT) were incorporated within the polymer films with the DBS to give PPy-DBSCNT (polypyrrole films doped with DBS and incorporated CNT). The polymer films were deposited from a 0.05 M DBS solution at a pH of 6.0 at a thin polypyrrole film doped with tartrate, which served as a stable pre-layer. Low corrosion currents of 0.12 and 0.05 μA cm−2 were estimated using Tafel analysis for the PPy-DBS and PPy-DBSCNT films, respectively, while a significant reduction in the concentration of Cu2+ ions from the corroding copper was observed for the polymer-modified copper. The corrosion protection properties were attributed to the doping of the polymer by the large and immobile DBS anions and possibly, by the larger anionic micelles that are formed at a DBS concentration of 9.8 mM in the pyrrole-containing solution. These dopants give a negatively charged surface that repels chloride anions. The additional protective properties afforded by the CNTs appear to be related to the morphology of the CNT-modified polypyrrole coatings, while the functionalized CNTs also provide a negatively charged surface.

scholarly journals Characterization and Control of the Wettability of Conducting Polymer Thin Films

2009 ◽  
Vol 1228 ◽  
Author(s):  
Jean H. Chang ◽  
Ian W Hunter
Keyword(s):  
Contact Angle ◽  
Surface Energy ◽  
Conducting Polymer ◽  
Water Contact Angle ◽  
Water Contact ◽  
Liquid Lenses ◽  
Polypyrrole Films ◽  
Electrochemically Deposited ◽  
Polypyrrole Film ◽  
And Control

AbstractThe wettability of electrochemically deposited conducting polymer films is highly dependent on several parameters including the deposition conditions, the dopant, and the roughness of the working electrode. To produce superhydrophobic surfaces, one must be able to control the micro and nanostructure of the film. In this study, a template-free method of producing superhydrophobic (water contact angle of 154°) polypyrrole films was demonstrated. The polypyrrole was doped with the low surface-energy heptadecafluorooctanesulfonic acid and had microstructures with nanometer-scale roughness. The microstructures served to increase the roughness of the film and amplify the hydrophobicity of the surface. It is also of interest to be able to dynamically adjust the wettability of a polypyrrole surface after deposition. Applications of this functionality include microfluidics, self-cleaning surfaces, liquid lenses, and smart textiles. By oxidizing or reducing a polypyrrole film, one can change the surface morphology as well as the chemical composition, and control the wettability of the surface. This study characterizes the electrochemically-induced changes in surface energy of polypyrrole. The relationship between applied voltage, charge transferred, surface roughness, and water contact angle was investigated. Upon reduction, the polypyrrole film was switched to a superhydrophilic state and the maximum change in contact angle was observed to be 154°. Surface wettability was found to be not fully reversible, with some hysteresis occurring after the first electrochemical cycle.

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