Raman characterization of pseudocapacitive behavior of polypyrrole on nanoporous gold

Abstract

The practical applications of high-capacitance polypyrrole (PPy) as an active material for electrochemical supercapacitors are mainly limited by their poor cycling stability. By utilizing nanoporous gold enhanced Raman scattering of PPy, we investigated ex situ and in situ the structural origins of the low electrochemical stability of PPy. This study provided direct evidence that the stability degradation of PPy is caused by the irreversible transition between oxidation and reduction states of PPy, which is associated with the permanent deformation of PPy molecular chains subjected to applied potentials.

In-situ deposition of polyaniline and polypyrrole electroconductive layers on textile surfaces by the reactive ink-jet printing technique

“…4.2 (comparison of the signal amplitudes). Significantly a more intense Raman line of 936 cm À1 than one of 973 cm À1 reveals that the PPy printed on PAN textile is obtained in polarons rather than in bipolarons [36][37][38].…”

“…It is sensitive to oxidation or reduction states [36,37], the presence of polarons and bipolarons [36][37][38] and of course to polymer conformation. All these aspects are interdependent, so interpretation of the Raman spectrum of PPy is not easy.…”

“…An assignment of particular modes to the polymer structure was based on [33][34][35]. Bands characteristic of polaron and bipolaron forms were based on [36][37][38]. Raman bands characteristic of reduced and oxidized states of PPy were based on [36][37][38].…”

“…Bands characteristic of polaron and bipolaron forms were based on [36][37][38]. Raman bands characteristic of reduced and oxidized states of PPy were based on [36][37][38].…”

Effects of radio frequency power on the microstructures and properties of plasma polymerized polypyrrole thin films

“…These types of sensors are experimentally proved to be effective in detecting alcohol, glucose, immunoglobulin G, anions, cations, volatile organic gases etc., as reported from massive studies in the literature. As examples, the design and fabrication of some specific sensors using polypyrrole can be found in [8][9][10][11][12][13][14][15], just to name a few. The review articles in [3][4][5][6] are excellent works to discuss some recent developments and sample works for biomedical related applications.…”