An Application of Conducting Polymer Polypyrrole for the Design of Electrochromic pH and CO₂Sensors

Abstract

In this research, conducting polymer -polypyrrole (Ppy), was electrochemically polymerized on the indium tin oxide coated glass (glass/ITO) electrode. The adhesion of Ppy on the surface of ITO was improved by modification with triethoxymethylsilane (TEMS). Potential cycling was applied for electrochemical deposition of Ppy layer and cyclic voltammograms were recorded during the deposition to monitor polymerization process. Cyclic voltammetry and the potential pulse sequence (PPS)-based chronoamperometry methods complemented the registration of absorbance spectra of glass/ITO (TEMS) /Ppy at various pH and different concentrations of CO 2 . The applicability of glass/ITO (TEMS) /Ppy electrode in the design of electrochromic sensor sensitive toward CO 2 has been evaluated. Cyclic voltammetry based experiments at different potential sweep rates in presence and absence of CO 2 were performed in order to evaluate charge transfer phenomenon in glass/ITO (TEMS) /Ppy structure.

Advances in Molecularly Imprinted Polymers Based Affinity Sensors (Review)

“…Sensing structures based on CPs can be formed by oxidative-chemical polymerization initiated by oxidizing compounds such as FeCl 3 , which was the most frequently used for the formation of conducting polymer–polypyrrole (Ppy). Some years ago, we have proposed to apply H 2 O 2 as initiator/oxidator in the formation of polyaniline [ 36 , 37 , 38 ] ( Figure 1 and Figure 2 ), polypyrrole [ 27 , 38 , 39 ] ( Figure 2 ), polythiophene [ 38 , 40 ] ( Figure 2 ), nanobiocomposite based on poly(1,10-phenanthroline-5,6-dione), poly(pyrrole-2-carboxylic acid) [ 41 ], poly-9,10-phenanthrenequinone [ 42 ], polyphenanthroline [ 21 ], carbazole [ 43 ], azobenzene [ 44 ] and some other conducting polymers.…”

“…Hence, electro-deposition of CP-based structures offers many possibilities for the design of sensors with tunable analytical characteristics. In addition to above mentioned advantages, there are many other serious reasons to choose electropolymerization for the formation of CP-based layers, because: this technique is much faster than the classical oxidative-chemical polymerization in the bulk but also it can be carried out in situ on the working electrode’s surface [ 73 ], and if potentiostat/galvanostat is controlled by properly developed software, then the whole process can be clearly observed on computer screen and evaluated/controlled using elaborated mathematical algorithms [ 12 ], The most recently used electrochemically deposited polymers are: polyaniline [ 36 , 56 ], polypyrrole [ 1 , 12 , 16 , 19 , 22 , 23 , 35 , 39 ], polythiophene and poly(3,4-ethylenedioxythiophene) (PEDOT) derivatives [ 36 , 74 ], Poly-9,10-phenanthrenequinone [ 42 ], In addition, some derivatives of these polymers can be electropolymerized and/or electro-copolymerized with some other monomers, which themselves are also forming conducting polymers, e.g., polypyrrole was copolymerized with other polypyrrole derivatives containing different 4-(pyrrol-1-yl)-benzenethiol groups and such copolymer was showing some properties desired for the application in sensors and biosensors [ 75 ].…”

“…Electrochromism is another important opto-electrochemical characteristic of many CPs that can be well adapted for the design of affinity sensors [ 137 ]. Electrochromic effect is a reversible variation of some optical characteristics if material is oxidized or reduced by applied electrical potential/current and materials that are changing their visible color are considered as electrochromic, therefore, some such materials like metal oxides (WO 3 [ 145 ]) and conducting polymers (PANI [ 137 ], Ppy [ 39 ] PEDOT/PSS [ 137 ] etc.) can be applied for the design of sensors.…”

Conducting Polymers in the Design of Biosensors and Biofuel Cells

“…A variety of conducting polymer synthesis techniques have been developed. Some very simple synthesis protocols have been reported by our research group, e.g., basic chemical and easily degradable agents such as hydrogen peroxide can be applied for the synthesis of conducting polymer (polypyrrole) [ 139 ], polyaniline [ 37 , 140 ], polythiophene [ 38 ], polyphenanthroline [ 9 ], nanobiocomposite based on poly(1,10-phenanthroline-5,6-dione), poly(pyrrole-2-carboxylic acid) [ 141 ], poly-9,10-phenanthrenequinone [ 39 ], carbazole [ 142 ], azobenzene [ 143 ], and some other conducting polymers. Some conducting polymers possess low cost, good environmental stability, and tunable properties [ 5 ], and they can form a number of various composites with organic [ 144 ], inorganic [ 145 ], and biological materials [ 145 ], which broadens the range of applicability for such composite materials based on the conducting polymers.…”

Effect of Electrosynthesis Potential on Nucleation, Growth, Adhesion, and Electronic Properties of Polypyrrole Thin Films on Fluorine-Doped Tin Oxide (FTO)

“…Since the discovery of intrinsically conductive polymers (ICPs) by Shirakawa et al in the 1970s [ 1 ], significant efforts have been made to understand the properties of these materials that combine the characteristics of metals and plastics. Over time, potential applications have been investigated in several areas where ICPs perform as functional materials, for example, batteries [ 2 , 3 , 4 ], solar cells [ 5 , 6 , 7 ], electrochromic devices [ 8 , 9 , 10 ], sensors [ 11 , 12 , 13 ], and more recently in photocatalysis and photoelectrochemistry [ 14 , 15 , 16 , 17 , 18 ]. Commonly, the performance of ICPs is strongly related to their morphology, redox state, and structural order (chain arrangement and conjugation length) as these parameters influence the surface area, electronic, and optical properties of the polymers [ 19 , 20 ].…”