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International audience; In this study, electrochemical behavior of different functionalized carbazoles has been studied through classical cyclic voltammetry, computational calculations, electrochemical simulations and more originally fast cyclic voltammetry. Indeed, fast electrochemistry is rarely used to study reactivity of such compounds even if it can bring very interesting information as shown in this work. Carbazoles were substituted with ethyl, tert-butyl and phenyl groups at 3 and 6 positions. Oxidation of 3-ethylcarbazole leads to very fast dimerization of formed radical cations (kdim = 1.5.107 M−1.s−1) and electrochemical polymerization of this compound leads to a thick adherent conducting polymer film. This was also the case for 3-phenylcarbazole and 3,6-diphenylcarbazole when potential was brought over 1.7 V/SCE because of formation of very reactive radicals after oxidation process involving phenyl groups. For 3,6-diethylcarbazole, 3-tert-butylcarbazole, 3,6-ditert-butylcarbazole, as well as 3-phenylcarbazole and 3,6-diphenylcarbazole when potential is kept under 1.4 V/SCE, dimerization of radical cations is slower (kdim ≤ 1.5.106 M−1.s−1) and no efficient electropolymerization occurs.A theoretical study of the same substituted carbazoles in their neutral and oxidized states was done using molecular orbital calculations (DFT method) to obtain additional information about carbazole reactivity. These numerical calculations were in perfect accordance with results of fast electrochemistry and electrochemical simulations regarding stability of radical cations. They demonstrated that monosubstituted carbazole dimers are probably obtained through 6-6′ coupling while 1-1′ coupling is the most favorable for disubstituted carbazole dimers.

The new terpyridine derivative 4’-(tellurophen-2-yl)-2,2′:6′,2″-terpyridine and its homoleptic Ru(II) complex have been prepared and characterized by different techniques (NMR, UV–Vis, mass spectrometry). Additionally, a thin polymer film was obtained through electrochemical oxidation and coupling of tellurophene moieties. The obtained organic coating showed very interesting electrochemical and electrochromic properties, thanks to its Ru(terpy)2 groups.

International audience; Interaction between ammonium pyrrolidinedithiocarbamate (PDTC) and bronze in 30 g L-1 NaCl was investigated at several concentrations between 0.1 and 10 mM by means of various electrochemical and spectroscopic techniques. Electrochemical measurements revealed a fast adsorption process of PDTC on Cu and Pb and the formation of a thick insulating and protective film with a high surface coverage. At high concentrations, PDTC prevents oxides formation. Surface analyses confirm PDTC adsorption on bronze mainly via interaction between sulphur atoms and Cu sites to form Cu I-PDTC complex.

Polycarbazole and its derivatives have advantages of good environmental stability, electrochromic properties and photoconductivity which have attracted considerable attention because of their potential industrial applications in electroluminescent applications, rechargeable batteries, and light emitting diodes. They have the possibility of different position substitution (carbon C3-C3' or N) that lead to different electropolymerization behaviors. However, the N position facilitates the grafting of various derivatives of interest and permits not to modify so much the radical cation formation during electropolymerization. In this paper, carbazole and its derivatives were electrochemically oxidized in acetonitrile solutions leading to the formation of thin polymer films. The morphological features and electrochemical properties of the as-formed polymer films were investigated in detail. Thanks to these experiments, the influence of the substitution on the properties of the polymer films was evidenced and discussed. In addition, fast electrochemistry experiments were carried out on platinum microelectrodes within 50–1,000 V/s scan speed range. Reactivity of carbazole derivatives radical cations and dimers was investigated through these experiments. Thermodynamic and kinetic information (e.g., redox standard potential, heterogeneous, and dimerization rate constants) was extracted after coupling with electrochemical simulations.

"The original publication is available at www.springerlink.com"; International audience; Effect of 2,5-dimercapto-1,3,4-thiadiazole (DMTD) concentration on the electrochemical behaviour of bronze was studied in 30 g L-1 sodium chloride (NaCl) by means of surface analyses and electrochemical techniques. Scanning Electron Microscopy (SEM) was used to observe surface morphology. Raman micro-spectroscopy was carried out to study chemical structure of deposited layers. X-ray photoelectron spectroscopy (XPS) enabled elemental characterization as well as molecular structure investigation. Finally, electrochemical polarization and impedance permitted a thorough study of corrosion protection behaviour reached through the presence of DMTD based organic layers on the surface. Above 1 mM, a fast adsorption of DMTD on copper (Cu) and lead (Pb) allows a thin and blocking film to be formed on bronze surface. DMTD prevents oxide formation at high concentrations and the surface film is mainly composed of Cu I-DMTD and Cu II-DMTD complexes as evidenced by spectroscopic techniques, with a bidentate adsorption at 1 mM and monodentate adsorption at 10 mM.

In this work, the friction and wear behavior of bare copper was investigated for the first time under lubricated sliding conditions in diluted ethanol solutions of butylhosphonic (C4P), octylphosph ...

For the first time, we have investigated the beneficial effects of non-cavitating coupling fluids and their moderate overpressures in enhancing mass-transfer and acoustic energy transfer in a double cell micro-sonoreactor. Silicon and engine oils of different viscosities were used as non-cavitating coupling fluids. A formulated monoethylene glycol (FMG), which is a regular cooling fluid, was also used as reference. It was found that silicon oil yielded a maximum acoustic energy transfer (3.05 W/cm2) from the double jacketed cell to the inner cell volume, at 1 bar of coupling fluid overpressure which was 2.5 times higher than the regular FMG cooling fluid. It was also found that the low viscosity engine oil had a higher acoustic energy value than that of the high viscosity engine oil. In addition, linear sweep voltammograms (LSV) were recorded for the quasi-reversible Fe2+/Fe3+ redox couple (equimolar, 5 × 10−3 M) on a Pt electrode in order to determine the mass-transport limited current density (jlim) and the dimensionless Sherwood number (Sh). From the LSV data, a statistical analysis was performed in order to determine the contribution of acoustic cavitation in the current density variation |Δj|average. It was found that silicon oil at 1 bar exhibited a maximum current density variation, |Δj|average of ~2 mA/cm2 whereas in the absence of overpressure, the high viscosity engine oil led to a maximum |Δj|average which decreased gradually with increasing coupling fluid overpressure. High viscosity engine oil gave a maximum Sh number even without any overpressure which decreased gradually with increasing overpressure. The Sh number for silicon oil increased with increasing overpressure and reached a maximum at 1 bar of overpressure. For any sonoelectrochemical processes, if the aim is to achieve high mass-transfer and acoustic energy transfer, then silicon oil at 1 bar of overpressure is a suitable candidate to be used as a coupling fluid.

Self-assembling of undecanthiol (C11SH) on polycrystalline gold was investigated under two different conditions. The kinetics of C11SH grafting was studied without and under high frequency ultrasound irradiation. Two electrochemical experiments were extensively carried out in order to determine electrochemical surface blocking of adsorbed layers as a function of grafting time: chronoamperometry in-situ monitoring and cyclic voltammetry. Interestingly, the grafting process is highly accelerated under sonication, and C11SH modified substrates of good quality are obtained after 3h' immersion under ultrasound irradiation. This would allow elaboration of high-quality alkanethiol modified samples within much shorter times. Water contact angle measurements and X-ray Photoelectron Spectroscopy (XPS) confirmed the presence of adsorbed undecanthiol on the gold surface. A very close link between electrochemical blocking, surface hydrophobicity and species chemical grafting was established.

Surface irradiation by power ultrasound has proven to offer beneficial effects not only for surface cleaning, but also for the modification of functional properties of metallic or organic coatings. However, the process scale-up has failed to match laboratory observations and data, in particular for the design of industrial sono-reactor systems. To solve this problem, electrochemical systems have been developed and used as effective sensors for ultrasonic activity allowing numerous useful quantitative information to help designing better sono-reactor and process control. Moreover, new types of ultrasonic transducers (e.g., focalised ultrasonic transducers) and new progress in the modulation of ultrasonic transducer excitation have pave the way to industrialization. © 2018. This is the authors' accepted and refereed manuscript to the article. The final authenticated version is available online at: http://dx.doi.org/10.1149/2.F05183if

Two different multilayered composite polypyrrole/SiO2 coatings were synthesized on 304 stainless steel. Electrochemical and electrophoretic depositions were used to grow polypyrrole and SiO2 layers, respectively. Coatings were characterized by glow discharge optical emission spectroscopy to observe repartition of elements within different layers, by scanning electron microscopy to observe surface morphology and by electrochemistry to investigate corrosion protection behavior. The electrophoretic approach enables good incorporation of SiO2 particles. This incorporation was more extensive and more homogeneous than for coatings obtained with the mixing method related in previous works. Moreover, incorporation and repartition of SiO2 particles are greatly enhanced when the silica layer is grown directly on the steel surface. Corrosion protection of the stainless steel substrate was improved when multilayered composite polypyrrole/SiO2 coatings were used.

For the first time, a terpyridine ligand bearing a selenophene ring at position 4′ was synthesized. It was then used to prepare an homoleptic Ru(II) complex with two pendant heterocycles that can undergo electrochemical polymerization to form a metallopolymer with metallic centres inside the backbone, each metallic units being connected via a diselenophene bridge. At the electrode surface, the polymer is present as a red thin film and was characterized by different analytical techniques, such as electrochemistry, XPS and AFM. Preliminary results show that the film exhibit electrochromism turning from red to yellow, a property that could be interesting for the design of functional materials.

Rare are the industrial examples of ultrasonic enhancement of the plating step itself. However, it has been demonstrated at laboratory scale that many advantages may be gained by use of ultrasound. Several authors such as Walker et al. (1973) [1] or Touyeras et al. [2] reported the beneficial effect of ultrasound in metal deposition and plating. This is particularly competitive as it may result in a reduction of chemical additives use, or even in their complete suppression. They also report that plating in an ultrasonic field may produce electrodeposits with an increased hardness and brightness, better adhesion to substrate, a finer grain and a reduced porosity and internal stress. Most of these properties are in direct relationship with the coating microstructure, which becomes therefore a major issue. Silver coating microstructures examined by XRD measurements reveals an important sensitivity of the crystalline preferential orientation to both current density and ultrasonic irradiation. Two main categories are identified by XRD: one poorly structured and the other following the [110] orientation, corresponding to low and high current densities. It is interesting to note that, while changing from still to mechanically stirred conditions, the value of the current density threshold moves from 2.5mA/cm² to 5mA/cm². When ultrasound is used (575 kHz or 20 kHz), this coating microstructure modification threshold occurs at higher current density values when coatings are produced under sonication, while agitation is kept at the same level (equivalent velocity). In both cases, the shift is about 15 mA/cm² [3]. It appears then as an interesting challenges to control the cavitation activity and especially the respective contribution from ultrasonic streaming vs. bubble collapse at the electrode vicinity [4]. This is possible by the use of the double reactor Besançon cell, filled with ionic liquids [5]. As ionic liquids present very low volatilities, their vaporization is reduced, and cavitation bubbles only depend on the presence of gases. Then, cavitation activity may be trigged by reactor atmosphere control. Applying severe depression within an irradiated ionic liquid medium contributes to removing dissolved gases, thus quenching progressively cavitation activity [6]. Electrolytes were prepared by dissolution of metallic salts composed by Tf2n as anion, and Copper or silver as cation in BuMIMTf2n, and deposits have been elaborated under various pressures (88, 55 and 26 kPa) to allow a progressive variation of the cavitation activity. All electrodepositions have been performed at a given potential, under the very same ultrasonic transmitted power. The charge was adapted to get the same thickness, and XRD measurements allow the comparison of crystalline preferential orientations. [1] C.T. Walker, R. Walker, Effect of ultrasonic agitation on some properties of electrodeposits, Electrodepos. Surf. Treat. 1 (1973) [2] F. Touyeras, J.Y. Hihn, X. Bourgoin, B. Jacques, L. Hallez, V. Branger, Effects of ultrasonic irradiation on the properties of coatings obtained by electroless plating and electro plating, Ultrason. Sonochem. 12 (2005) [3] A. Nevers, L. Hallez, F. Touyeras, J.-Y. Hihn, Effect of ultrasound on silver electrodeposition: Crystalline structure modification, Ultrason. Sonochem. 40 (2018) [4] J.-Y. Hihn, M.-L. Doche, A. Mandroyan, L. Hallez, B.G. Pollet, Respective contribution of cavitation and convective flow to local stirring in sonoreactors, Ultrason. Sonochem. 18 (2011) [5] C. Costa, J.-Y. Hihn, M. Rebetez, M.-L. Doche, I. Bisel, P. Moisy, Transport-limited current and microsonoreactor characterization at 3 low frequencies in the presence of water, acetonitrile and imidazolium-based ionic liquids, Phys. Chem. Chem. Phys. PCCP. 10 (2008) [6] B. Naidji, L. Hallez, A. EtTaouil, M. Rebetez, J.-Y. Hihn, Influence of pressure on ultrasonic cavitation activity in room temperature ionic liquids: An electrochemical study, Ultrason. Sonochem. 54 (2019) Figure 1

Surface irradiation by power ultrasound has proven to offer beneficial effects not only for surface cleaning, but also for the modification of functional properties of metallic and organic coatings. However, the process scale-up has failed to match laboratory observations and data, in particular for the design of industrial sono-(electro)chemical reactor systems. To solve this major problem, electrochemical systems have been developed and employed as effective “sensors” for probing ultrasonic activity, in turns allowing numerous useful quantitative information to aid designing better sono-(electro)chemical reactor and process control. Indeed, it is possible to use electrochemistry as a tool to investigate phenomena occurring at the electrode surface and at a given location in the sono-(electro)chemical reactor. From a process accelerated by power ultrasound, electrochemistry becomes a very useful tool to quantify the ultrasonic energy (and power) scattered at the immediate working electrode surface vicinity. The electro-diffusional method is of great help, as it consists of measuring limiting currents generated by Linear Sweep Voltammetry (LSV) experiments. This approach has turned out to be extremely efficient and useful for the determination of acoustic intensity at various locations in the sono-(electro)chemical reactor [1]. By systematically moving a working electrode in an ultrasonic field, it is possible to map out the acoustic activity, especially in the zone close to the ultrasonic transducer where the most intense cavitation activity takes place. Then, to demonstrate the ‘portability’ of our generated data, i.e. to allow relevant comparisons between experiments performed using different ultrasonic and electrochemical equipment, we have proposed to convert the raw electrochemical values into equivalent velocities U, corresponding to normal flows directed towards the working electrode surface resulting in the same electrochemical signal than in the presence of power ultrasound [2]. Comparisons with ‘real fluid motion’ at a given location with the help of Particle Image Velocimetry (PIV) technique allows separation of the respective contributions of cavitational events occurring at the working electrode surface to the convection flow called ultrasonic wind [3]. This approach has been extended to several electrochemical systems. Moreover, new types of ultrasonic transducers (for example, focalized ultrasonic transducers) and new progress in the modulation of ultrasonic transducer excitation have pave the way to industrialization of sono-(electro)chemical reactors [4]. [1] Hihn J.-Y., Doche M.L, Mandroyan A., Hallez L. and Pollet B.G., Chapter 23 "Ultrasound and Better Reactor design" in Handbook on Applications of Ultrasound: Sonochemistry for sustainaibility by CRC Press Taylor & Francis, 2011, p599-622 [2] Pollet B.G., Hihn J.-Y., Doche M.L, Mandroyan A., Lorimer J.P., Mason T.J “Transport limited currents close to an ultrasonic horn: equivalent flow velocity determination”, Journal of Electrochemistry Society, 2007, 154(10), p E131-E138 [3] J.Y. Hihn, M.L. Doche, A. Mandroyan, L. Hallez, B.G. Pollet, "Respective contribution of cavitation and convective flow to local stirring in sonoreactors" Ultrasonics Sonochemistry 18(4), 881-887, (2011) [4] Hallez L., Lee J., Touyeras F., Nevers A., Ashokkumar M., Hihn J.-Y., “Enhancement and Quenching of HIFU Cavitation Activity via Short Frequency Sweep Gaps”, Ultrasonics Sonochemistry, 2016, 29, p. 194-197 Figure 1

Chemical effects of ultrasound on conducting polymers were studied, especially the effects of OH• radicals. In spite of OH• radicals formation by ultrasound, electroactivity of sonicated films is not degraded. That was explained by the too low concentration of these active species generated in irradiated media. These same radical species are, for the first time, claimed to be at the origin of the increase in doping level which has always been observed for conducting polymer films grown under ultrasound irradiation.

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International audience; A metal-containing polymer has been prepared by electropolymerization of an homoleptic Ru(II)-terpyridine complex bearing pyrrole heterocycles. The polymer is obtained as a thinfilm at the surface ofelectrodes, and has been characterized by electrochemical measurements, XPS and microscopy. It hasbeen shown that this polymer acts as an active gas sensitive layer since it enables the detection of anammonia gasflow through layer’s resistivity measurements.

International audience; Self-assembly of alkylphosphonic acids on stainless steel was investigated under different conditions. Four different alkylphosphonic acids exhibiting alkyl chain of various size were synthesized and studied: butylphosphonic acid (C4P), octylphosphonic acid (C8P), decylphosphonic acid (C10P), and hexadecylphosphonic acid (C16P). Electrochemistry experiments were extensively carried out in order to determine electrochemical surface blocking of adsorbed layers in function of grafting time. In term of surface blocking, an 8h modification time was optimal for all alkylphosphonic acids. Longer immersion times lead to degradation of adsorbed layers. For the first time, grafting of C16P was studied under high frequency ultrasound irradiation. Interestingly, grafting process is highly accelerated under sonication and well-covering C16P modified substrates are obtained after 1h of immersion under ultrasound irradiation. This would allow to elaborate high-quality alkylphosphonic acids modified samples within much shorter times. Water contact angles measurements and X-ray Photoelectrons Spectroscopy (XPS) confirmed presence of adsorbed alkylphosphonic acids on stainless steel surface. A very tight link between electrochemical blocking, surface hydrophobicity and species chemical grafting was established.

International audience; This paper presents electrochemical synthesis of polypyrrole films under high frequency sonication. The films are characterized in terms of adhesion and surface morphology. Comparison to classical electrosynthesized polypyrrole films is made. In particular, the use of high frequency sonication (500 kHz) during electrodeposition of polypyrrole on Si was reported for the first time. Chronocoulometry was used for polymer films electrosynthesis on Si substrates. Influence of polymer thickness on the rugosity, morphology and adhesion force properties was studied. Scanning Electron Microscopy and mechanical probe profiling showed that sonication led to less rough and more homogeneous surface structure. Adhesion force properties of polypyrrole films were also studied by means of force-distance curves obtained by atomic force microscopy. For polymer films obtained in the absence of sonication, adhesion forces decreases with increase in polymer thickness. On the contrary, for polymer films obtained under sonication, the adhesion of the films decreased when the polymer thickness decreased.

The propagation of an acoustic wave into a solution can lead to the break of liquid cohesion strengths. This results in the nucleation, growth and collapse of cavitation bubbles feed by solvent vapors and dissolved gases. This collapse may be beneficial as in the case of cleaning processing, but is clearly detrimental in some application as in the case of therapeutic treatments such as tumor ablation, or for the ultrasonic power transmission in coupling fluids. For the electrochemical processes assisted by ultrasound, its control is mandatory. Then, this phenomenon must be reduced by the application of over-pressures into the reactors [1]. To be able to determine the respective contributions of dissolved gases and of vapors into the cavitation bubble collapse, the present work will seek the effect of a limitation in dissolved gases into a sonoreactor by controlling the pressure in a low vapor pressure media: ionic liquids. Those solvents are constituted of a dissymmetric anion and cation, are liquid at room temperature, and show excellent properties for our tests such as a great conductivity. As their vapor pressure is exceptionally low, only the dissolved gases will contribute to the cavitation: as the content in dissolved gas is driven by the pressure, its reduction will result in a reduction of the cavitation activity. In order to quantify this level, the diffusion study of electrochemical species was used as mass transfer sensor [2]. An electroactive species (Ferrocene) forming a rapid and reversible system is present in the solution at low concentration, and in presence of ultrasound, two contribution to the current in steady state conditions can be observed: one depending of the time and the other independent. Both are respectively proportional to the flow generated by the acoustic convection and to the bubble collapse at the electrode interface. The results show an important decrease of the cavitation phenomenon for argon pressure lower than 0.6 bar. A mathematical treatment of the curves allows the extrapolation up to the absolute cavitation quenching, at which the single contribution comes from convection. [1] Parag R. Gogate, Aniruddha B. Pandit. 2005, Ultrasonic Sonochemistry , 12 , 21_27. [2] Pollet B.G.,Hihn J-Y.,Doche M.L., Mandroyan A., Lorimer J-P., Mason T.J. 2007 , Journal of Electrochemistry Society, 154 , 131-138. Figure 1

This paper deals with the effect of ultrasound on polypyrrole/SiO2 composite film elaboration through various steps (particle dispersion, electrosynthesis). Experiments were carried out on stainless steel in phosphoric acid solution. An efficient method for dispersion of SiO2 particles prior to electropolymerization, based on low frequency irradiation (20 kHz), was proposed. It was shown that mechanical effects of high frequency ultrasound (i.e. mass transfer improvement) led to enhancement of electropolymerization kinetics. Scanning electron microscopy imaging and glow discharge optical emission spectroscopy revealed localization of SiO2 particles in the outer region of the films as well as better incorporation of particles under high frequency ultrasound irradiation. Finally, anticorrosion behavior of formed films was investigated in sodium chloride solution by Open Circuit Potential and anodic polarization methods. The results showed that polypyrrole/SiO2 films elaborated under ultrasound irradiation exhibit the best protective performances.

In this review paper, the classical and more recently described mechanisms responsible for the structural and functional characteristics of large artery rigidity are described. Mostly important, these characteristics appear to be nonspecific to the primary disease process involved in arterial hypertension, diabetes mellitus, dyslipidemia, congestive heart failure, chronic uremia, and perhaps senescence, including vascular dementia. Nonspecific in terms of aetiology, the vasculopathy encountered in these diseases exhibits common structural and functional abnormalities. The identification of such abnormalities could well become the target of potent nonpharmacological and (or) pharmacological interventions capable of preventing or retarding morbidity and mortality. The structural characteristics responsible for large artery rigidity include smooth muscle cell hypertrophy, matrix collagen deposition, and recently described, dysfunction in proteoglycan metabolism. Functional abnormalities, such as bradykinin-dependent hyper-reactivity of smooth muscle cells and vasa vasorum microcirculation network disturbances, also appear to alter aortic wall rigidity. The physiopathology of target organ damage is then revisited, based on endothelial dysfunction, documented in large and resistance arteries, as well as in microcirculation networks, where altered permeability to macromolecules leads to interstitial matrix disorganization and cell damage. The clinical evaluation of large artery rigidity is described, and one of the noninvasive methods, evaluation of pulse-wave velocity, is validated in normal conditions and in disease processes. Finally, nonpharmacological and pharmacological therapeutic measures are presented, and includes physical exercise to reduce insulin resistance, and renin–angiotensin-II–aldosterone modulators.Key words: large artery compliance, aortic structure, collagen, elastin, proteoglycans, vascular smooth muscle cells, vasa vasorum, target organ damage, pulse wave velocity, vascular pharmacology.

International audience; Electron transfer inside proteins plays a central role in their reactivity and biological functions. Herein, we developed a combined approach by gamma radiolysis and electrochemistry which allowed a deep insight into the reactivity of Human centrin 2, a protein very sensitive to oxidative stress and involved in several key biological processes. This protein bears a single terminal tyrosine and was observed to be extremely sensitive to ionizing radiation sources, leading to a tyrosine dimer. By cyclic voltammetry in the 100-1000 V s(-1) range, its redox potential and dimerization rate could be evaluated. Accordingly, reaction in solution with a redox mediator revealed an efficient catalysis. Finally, protein denaturation by a progressive increase in temperature was proportional to a decrease of dimerization radiolytic yield. Our results thus demonstrated that the protein structure plays a major role in oxidation sensitivity. This leads to meaningful results to understand protein redox reactivity.

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A variety of coatings based on electrosynthesized polypyrrole were deposited on zinc coated steel in presence or absence of ultrasound, and studied in terms of corrosion protection. Cr III and Cr VI commercial passivation were used as references. Depth profiling showed a homogeneous deposit for Cr III, while SEM imaging revealed good surface homogeneity for Cr VI layers. These chromium-based passivations ensured good protection against corrosion. Polypyrrole (PPy) was also electrochemically deposited on zinc coated steel with and without high frequency ultrasound irradiation in aqueous sodium tartrate–molybdate solution. Such PPy coatings act as a physical barrier against corrosive species. PPy electrosynthesized in silent conditions exhibits similar properties to Cr VI passivation with respect to corrosion protection. Ultrasound leads to more compact and more homogeneous surface structures for PPy, as well as to more homogeneous distribution of doping molybdate anions within the film. Far better corrosion protection is exhibited for such sonicated films.

This study deals with the effects of high frequency ultrasound (500 kHz) irradiation on the electrochemical synthesis of conducting polymers in aqueous media. Ultrasound favors electrochemical polymerization reaction by improving mass transfer of electroactive species towards the electrode. It leads to films more compact, presenting a thinner and more homogeneous topography. Chemical effects generated by the acoustic wave propagation enable a higher doping level for the films. However, their electrical conductivity is slightly reduced, due to partial degradation of polymer chains by cavitational activity. The possibility to control morphological properties was used in different applications such as potentiometric pH sensors or anti-corrosion coatings. For such applications, using these films as functional layers, the irradiated coatings lead to better results. A selective masking technique, based on focused ultrasound, has been developed as well in order to elaborate a biphased substrate permitting interesting biological applications; L’objectif de ces travaux est d’étudier les effets d’une irradiation ultrasonore haute fréquence (500 kHz) sur la synthèse électrochimique de polymères conducteurs en milieu aqueux. Les ultrasons favorisent la réaction de polymérisation électrochimique en augmentant le transport des espèces électroactives vers l’électrode. Ils engendrent des films plus compacts, présentant une topographie plus fine et plus homogène. Les effets chimiques engendrés par la propagation de l’onde acoustique permettent un meilleur taux de dopage des films. Néanmoins, leur conductivité électrique se trouve légèrement diminuée, dû à une dégradation des chaînes polymères par l’activité cavitationelle. La possibilité de contrôler les propriétés de morphologie fut mise à profit dans différentes applications comme celles des capteurs pH potentiométriques ou des revêtements anti-corrosion. Pour de telles applications, utilisant ces films en tant que couche fonctionnelle, les surfaces obtenues en présence d’irradiation ultrasonore mènent à de meilleurs résultats. Une technique de masquage sélectif à base d’ultrasons focalisés a également été développée afin d’élaborer un substrat biphasique laissant présager d’intéressantes applications biologiques

This study deals with the effects of high frequency ultrasound (500 kHz) irradiation on the electrochemical synthesis of conducting polymers in aqueous media. Ultrasound favors electrochemical polymerization reaction by improving mass transfer of electroactive species towards the electrode. It leads to films more compact, presenting a thinner and more homogeneous topography. Chemical effects generated by the acoustic wave propagation enable a higher doping level for the films. However, their electrical conductivity is slightly reduced, due to partial degradation of polymer chains by cavitational activity. The possibility to control morphological properties was used in different applications such as potentiometric pH sensors or anti-corrosion coatings. For such applications, using these films as functional layers, the irradiated coatings lead to better results. A selective masking technique, based on focused ultrasound, has been developed as well in order to elaborate a biphased substrate permitting interesting biological applications; L’objectif de ces travaux est d’étudier les effets d’une irradiation ultrasonore haute fréquence (500 kHz) sur la synthèse électrochimique de polymères conducteurs en milieu aqueux. Les ultrasons favorisent la réaction de polymérisation électrochimique en augmentant le transport des espèces électroactives vers l’électrode. Ils engendrent des films plus compacts, présentant une topographie plus fine et plus homogène. Les effets chimiques engendrés par la propagation de l’onde acoustique permettent un meilleur taux de dopage des films. Néanmoins, leur conductivité électrique se trouve légèrement diminuée, dû à une dégradation des chaînes polymères par l’activité cavitationelle. La possibilité de contrôler les propriétés de morphologie fut mise à profit dans différentes applications comme celles des capteurs pH potentiométriques ou des revêtements anti-corrosion. Pour de telles applications, utilisant ces films en tant que couche fonctionnelle, les surfaces obtenues en présence d’irradiation ultrasonore mènent à de meilleurs résultats. Une technique de masquage sélectif à base d’ultrasons focalisés a également été développée afin d’élaborer un substrat biphasique laissant présager d’intéressantes applications biologiques