Growth and Morphology of Polythiophene on Thiophene-Capped Monolayers:  1. Single Component Monolayers

Abstract

Thin polythiophene films were grown at a variety of oxidizing potentials by electrochemical polymerization on indium tin-oxide surfaces that were modified with a thiophene-capped, self-assembled monolayer (SAM) composed of 11-(3-thienyl)-undecyltrichlorosilane (3TUTS). The evolution of those growing films was tracked via cyclic voltammetry and infrared spectroscopy, and the surface morphology was probed with atomic force microscopy. To allow comparison, similar data were obtained for polythiophene films grown on bare indium tin-oxide (ITO) (no SAM). Our results show that 3TUTS layers can nucleate growth of polythiophene films at potentials below the oxidation potential of monomeric thiophene in solution, and the cyclic voltammetry signature is characteristic of a surface-confined, redox-reversible species; however, at these low potentials no polythiophene growth on the bare ITO electrodes is seen. At higher potentials where polythiophene growth is observed on both types of surfaces, an additional amount of charge corresponding to the amount of thiophene groups along the SAM is transferred across the SAM-modified electrodes. Although spectroscopic data reveal no differences in the films grown on bare and 3TUTS-modified ITO, atomic force microscopy results show that the latter class of films are more homogeneous, have lower roughness, and are denser than the corresponding film grown on bare ITO. We attribute this difference in the morphology of the films to the high nucleation density arising from the pendent thiophene rings of the monolayer.

Conducting polyfurans by electropolymerization of oligofurans

“… 24 To the best of our knowledge, the lowest r rms value obtained for electrodeposited PEDOT films in organic media is 46 nm. 25 c Smooth polythiophene films were obtained after modification of the working electrode, 24 , 44 while smooth electrodeposited PEDOT films were obtained from microemulsions in aqueous solution. 45 The polymer precursor approach ( i.e.…”

“…It is worth noting that the electrodes were not modified and specially cleaned as they were in the preparation of smooth polythiophenes. 24 Representative cyclic voltammograms (CV) for the polymerization of P3 (PFu 5 -C 8 ) on ITO electrode, showing stepwise increases in the current over the course of polymerization, are displayed in Fig. 1 (for other polymers see Fig.…”

“…It is worth noting that prepared polyfuran films have lower roughness than most other electrochemically-prepared films under similar conditions, 24 , 25c , 44 – 46 i.e. , in organic media electrolyte, in ambient environment, without electrode surface modifications and extensive electrode cleaning.…”

Development of an Electrochemical Sensor Using a Modified Carbon Paste Electrode with Silver Nanoparticles Capped with Saffron for Monitoring Mephedrone

“…In this study, poly-AgNPs@Sa was potentio-dynamially polymerized on CPE by scanning the potential in the range of −0.300 V to +1.3 V vs. Ag/AgCl and with a scan rate of 30 mV s −1 . It is worth mentioning that the CPE was not modified and specially cleaned, since it was meant to be used in the preparation of smooth poly-AgNPs@Sa deposits [52,53]. CVs of poly-AgNPs@Sa on CPE, presenting stepwise increases in the peak current over the polymerization process, are displayed in Figure 2.…”

The influence of doping ions on poly(3,4-ethylenedioxythiophene) as a counter electrode of a dye-sensitized solar cell

“…Similar results were observed in the 11-(3-thienyl)undecyltrichlorosilane modified ITO electrode when electropolymerizing polythiophene. 23 Surface morphology of different PEDOT films Fig. 2 shows the SEM surface morphologies of PEDOT based on the chemical oxidation method and electrochemical polymerization in the presence of different doping ions.…”