Regular poly(para-phenylene) films bound to gold surfaces through the electrochemical reduction of diazonium salts followed by electropolymerization in an ionic liquid

Abstract

To cite this version:Stéphanie Descroix, Géraldine Hallais, Corinne Lagrost, Jean Pinson. Regular poly(para-phenylene) films bound to gold surfaces through the electrochemical reduction of diazonium salts followed by electropolymerization in an ionic liquid. Electrochimica Acta, Elsevier, 2013, 106, pp.172-180 AbstractBy combining the electroreduction of diazonium salts and the electropolymerization of conducting polymers in an ionic liquid, the electrografting of a regular poly(para-phenylene) film on a gold substrate is achieved, leading to the strong and robust anchoring of the PPP polymers on the substrate (Au-PPP hybrid). A thin layer covalently bound to the substrate is first prepared by the reduction of benzenediazonium salt (BD), then, on top of this layer, a thicker layer of poly(para-phenylene) (PPP) is easily grown by the electrochemical oxidation of biphenyl in the [BMIm] [PF 6 ] ionic liquid. The resulting material is thoroughly characterized by IR, ToF-SIMS and fluorescence spectroscopies. The analyses show the formation of well regular PPP layers that are wired to the substrate. The key role of the [BMIm] [PF 6 ] ionic liquid in the structuration of the polymer is emphasized.

Functionalization of Carbon Materials by Reduction of Diazonium Cations Produced in Situ in a Brønstedt Acidic Ionic Liquid

“…After a thorough rinsing in pure water, the functionalized electrode was further studied in the aqueous H 2 SO 4 electrolyte and the characteristic peaks for the ‐NHOH/‐NO redox system were observed (Figure a), evidencing the grafting of the 4‐nitrobenzene groups onto the electrode. By taking into account for the high robustness of the surface‐organic layer interface induced by this functionalization route, a strong mechanical abrasion or washing with hot solvents are generally required to take out the organic layer . A very smooth wiping of the electrode surface for removing the deposited carbon nanotubes leads to an almost disappearance of the oxidation peak due to the attached hydroxylamine (Figure b).…”

“…By taking into account for the high robustness of the surface-organic layer interface induced by this functionalization route, as trong mechanical abrasion or washing with hot solvents are generally required to take out the organic layer. [14,23] Av ery smooth wiping of the electrode surfacef or removing the deposited carbon nanotubes leads to an almost disappearance of the oxidation peak due to the attached hydroxylamine ( Figure 7b). This observation suggests that the redox signal at 0.3 V( vs. SCE) is mostly due to the graftedc arbon nanotubes covering the BPG electrode surface.…”

“…[19] However,t he described approach requires the prior isolation of the diazonium salts, which could be at edious task while the in situ production of the diazonium cations makes the methodm uch more versatile. Yet, af ew examples has reported the use of room-temperature ionic liquidsa se lectrolyte for the electrochemical reduction of diazonium cations, [20][21][22][23] but only one example deals with the in situ productiono ft he diazonium cation by employing ap rotic ionic liquid formed by a1 :2 mixture of 4-methoxypyridine with trifluoroacetic acid. [20] However,such an ionic liquid materialiso bviously not relevant for dispersing and processing carbon nanotubes.…”

Grafting of 4-pyrrolyphenyldiazonium in situ generated on NiTi, an adhesion promoter for pyrrole electropolymerisation?

“…The use of grafted diazonium salt as adhesion promoter for the electropolymerisation of conducting polymers is well known [40][41][42][43]. Particularly, among the wide variety of monomers to generate conducting polymers, pyrrole is of particular interest mainly because of its relatively low oxidation potential (~ 0.8 V/SCE).…”

Electrosynthesis of poly(p-phenylene) and poly(p-phenylene/pyrrole) films under controlled humidity

“…Recent research on PPP has been directed at its use with LiH in hydrogen storage (Yoshida et al, 2014), as a prototype for optoelectronic devices (Talipov et al, 2014) and other devices after being electrografted onto Au electrodes (Descroix et al, 2013). In general, conducting polymers can be prepared as composites and modified materials after optimisation of the preparation conditions (Arslan & Hur, 2014;Stejskal, 2013).…”