Preparation and Characterization of a Lignin Modified Electrode

Abstract

Alkali lignin undergoes strong adsorption on polycrystalline gold electrodes. Subsequent oxidation in a sulfuric acid solution leads to a restructured redox-active polymer that shows features characteristic for surface confined species. Surface coverage of up to 4.40 Â 10 À10 mol cm À2 may be obtained depending on the adsorption time or lignin concentration in the adsorption solution. Using Lavirons approach the electron-transfer rate constant and the transfer coefficient were found to be 8.9 s À1 and 0.35, respectively. The formal potential of the redox couple shifted negatively with pH at a rate of ca. 60 mV/pH unit, suggesting a 2 e/2 H þ reaction. The redox couple was also found to be a good mediator for electrochemical ascorbic acid oxidation in neutral phosphate buffer with ca. 250 mV reduction of the oxidation overpotential.

Kraft lignin and silica as precursors of advanced composite materials and electroactive blends

“…The observed electrochemical activity of the KL-SiO 2 composite, especially that due to residual quinone moieties, point to the possibility of the application of such materials in electrochemical sensors for such applications as previously proposed [33,34,36].…”

“…It is noteworthy that with an increased amount of KL in the composite the cyclic voltammograms show a continuous increase in a reversible redox couple at the mean-peak potential of ca. 0.15 V, which can be attributed to the lignin-derived quinone moieties [1,[33][34][35][36].…”

“…Moreover, the biocompatibility and the easy chemical functionalisation of silica and silica-like thin films formed by sol-gel approaches have led to the use of such compounds as enzyme-grafting supports in electrochemical biosensors [32]. Similarly, lignins coming from various pulping processes have been shown to be applicable in electrochemical sensors owing to their residual quinone moieties, which are redox-and thus electroactive [33,34]. In order to intensify the chemical properties of lignins that make it suitable for electrochemical applications, various methods of combining these materials with electronic conductors (carbon nanotubes or conducting polymers) have been proposed [1,35,36].…”

Electrochemical study of Conducting Polymer/Lignin Composites

“…Papers are dedicated to the lignin oxidation on different electrodes for the sake of the development of a voltammetric lignin analysis method such as adsorption on polycrystalline gold electrodes 13 , Lignosulfonate modified glassy carbon electrode 14 , polypyrrole/lignin composite [15][16] , chloroaniline/lignin 17 have been discussed. This paper reports the successful preparation of composites modified electrode on glassy carbon electrode surface (LG/GCE, AHNSA/GCE, POPDA/ GCE, and its composite (LG-co-AHNSA and LGco-OPDA) by repetitive CV scans, to improve the electrochemical behavior of the prepared modified electrode by Cyclic voltammetry, Electrochemical Quartz Crystal Microbalance (EQCM) techniques and characterize with Fourier transform infrared spectroscopy (FTIR).…”

Chemistry of lignin-based materials

“…262 Other than the lignin-polypyrrole conjugated electrode, series of lignin-modifi ed electrodes were reported with showing high electrochemical activity and material stability. [269][270][271][272] As a none electrochemical applications of ligninpolyaniline composite, He et al recently reported that enzymatic hydrolysis lignin/polyaniline composite, which shows high-silverion adoption property on the composite surface. …”