Thin Functional Polymer Films by Electropolymerization

Abstract

Intrinsically conducting polymers (ICPs) have been widely utilized in organic electronics, actuators, electrochromic devices, and sensors. Many potential applications demand the formation of thin polymer films, which can be generated by electrochemical polymerization. Electrochemical methods are quite powerful and versatile and can be utilized for investigation of ICPs, both for educational purposes and materials chemistry research. In this study, we show that potentiodynamic and potentiostatic techniques can be utilized for generating and characterizing thin polymer films under the context of educational chemistry research and state-of-the-art polymer research. First, two well-known bifunctional monomers (with only two linking sites)—aniline and bithiophene—and their respective ICPs—polyaniline (PANI) and polybithiophene (PBTh)—were electrochemically generated and characterized. Tests with simple electrochromic devices based on PANI and PBTh were carried out at different doping levels, where changes in the UV-VIS absorption spectra and color were ascribed to changes in the polymer structures. These experiments may attract students’ interest in the electrochemical polymerization of ICPs as doping/dedoping processes can be easily understood from observable color changes to the naked eye, as shown for the two polymers. Second, two new carbazole-based multifunctional monomers (with three or more linking sites)—tris(4-(carbazol-9-yl)phenyl)silanol (TPTCzSiOH) and tris(3,5-di(carbazol-9-yl)phenyl)silanol (TPHxCzSiOH)—were synthesized to produce thin films of cross-linked polymer networks by electropolymerization. These thin polymer films were characterized by electrochemical quartz crystal microbalance (EQCM) experiments and nitrogen sorption, and the results showed a microporous nature with high specific surface areas up to 930 m2g−1. PTPHxCzSiOH-modified glassy carbon electrodes showed an enhanced electrochemical response to nitrobenzene as prototypical nitroaromatic compound compared to unmodified glassy carbon electrodes.

Electrodeposition of Mesoporous Ni-Rich Ni-Pt Films for Highly Efficient Methanol Oxidation

“…A thin layer could be observed on the FTO electrodes after 60 s of deposition at −1.3 V. However, no oxidation peaks—that is, neither O1 nor O2—were recorded when Si/Ti/Au was used as a working electrode. It is well known that FTO catalyzes the electrodeposition of various polymers such as polypyrrole, polyaniline, poly(3,4-ethylenedioxythiophene), and polybithiophene [ 39 , 40 , 41 ]. Consequently, the reduction peak observed with the THF (Bath 1), PS- b -PEO (Bath 2), and Ni (Bath 3) solutions can be assumed to indicate the simultaneous deposition of THF, PS- b -PEO, and/or Ni, depending on the system, as well as the hydrogen evolution reaction.…”

“…As a partial antidote, the block copolymer-templated electrodeposition has been revealed as a reliable strategy for synthesizing Au- or Pt-based architectures that provide uniform controllable mesoporosity on metallic substrates [ 21 , 24 , 25 , 26 , 37 , 38 , 39 ]. Even so, block copolymer-templated electrodeposition offers not only excellent control of pore size and wall thickness by varying the length of copolymer fragments, but also the final composition of deposits by adjusting the parameters of electrodeposition (e.g., bath composition, temperature, and applied potential).…”

“…As a result, the codeposition of mesoporous films can be accomplished by applying an electrochemical signal [ 21 , 24 , 25 , 26 , 37 , 38 , 39 ]. Nevertheless, its use in non-Pt- or Au-based materials is highly restricted, because only Ni or Cu films can be successfully synthesized [ 21 , 24 , 25 , 26 , 37 , 38 , 39 ]. Understanding the possibilities and limitations of block copolymer-templated electrodeposition and extending the usage to other materials and other substrates is still highly required for real applications.…”

Electrochemical DNA Sensor Based on the Copolymer of Proflavine and Azure B for Doxorubicin Determination

“…Electropolymerization is an advanced tool of modern electrochemistry that is frequently used for the modification of the electrodes in the assembly of electrochromic devices and electrochemical biosensors [1,2]. In these reactions initiated by primary electron transfer, oligomeric products are formed and deposited on the electrode as a dense uniform film, whose properties are derived from those of the monomers [3][4][5].…”

Spectroelectrochemistry of Selected Substances – A Contribution to Higher Education Didactics

“…Software ca. 250 USD kosten[51,52,53,54,55]. Derzeit laufen an der PH Ludwigsburg verschiedene Arbeiten, in denen spektroelektrochemische Experimente mit einer solchen Low-cost-Photometer/Potentiostat-Kombination durchgeführt werden.DanksagungDer Autor dankt der Vector-Stiftung (Stuttgart), dem Fonds der Chemischen Industrie (Frankfurt) und der Pädagogischen Hochschule Ludwigsburg für finanzielle Unterstützung sowie Frau Ramona Weiß, PH Ludwigsburg, für die Aufnahme einiger der Fotos.…”