Bisferrocenyl-functionalized pseudopeptides: access to separated ionic and electronic contributions for electrochemical anion sensing

Abstract

Pseudopeptidic receptors containing ferrocene fragments have been prepared and their response to a series of anions was measured by a voltammetry of microparticles methodology.

The Thermodynamics of Insertion Electrochemical Electrodes—A Team Play of Electrons and Ions across Two Separate Interfaces

“…This idea is further supported by the reversible proton response,w hich is ap artition of protons between the solution and the surface of the tungsten bronze,i nc lear analogy to the function of the glass electrode. [22] Thev oltammetric response,h owever,i sc aused by the transfer of electrons and protons.C learly,s ubtracting the standard potential of ion transfer (determined from the open-circuit potentials of the electrode in aqueous solutions containing protons) from the voltammetric standard potential, gives the standard potential for the pure electron transfer process.T he next lucky accident was to notice that certain solid gold complexes (Figure 4) [13] and pseudopeptides [23] possessing ferrocenyl units also exhibit areversible potentiometric and voltammetric response.…”

“…Clearly, subtracting the standard potential of ion transfer (determined from the open‐circuit potentials of the electrode in aqueous solutions containing protons) from the voltammetric standard potential, gives the standard potential for the pure electron transfer process. The next lucky accident was to notice that certain solid gold complexes (Figure ) and pseudopeptides possessing ferrocenyl units also exhibit a reversible potentiometric and voltammetric response.…”

Die Thermodynamik von insertionselektrochemischen Elektroden – ein Mannschaftsspiel über zwei separate Grenzflächen

“…[21] Abbildung 3zeigt schematisch das potentiometrische und voltammetrische Ansprechen der Wolframbronze:I mF all einer potentiometrischen Messung (praktisch stromlos) werden die Redoxzentren des Wolframs,d .h.W VI/V ,n icht verändert, sondern es findet nur eine Verteilung der Protonen zwischen der Lçsung und der Oberfläche der Wolframbronze statt, ganz analog zur Funktionsweise einer Glaselektrode. Ein zweiter glücklicher Umstand führte zu den in Abbildung 4g ezeigten Goldkomplexen [13] und zu Pseudopeptiden, [23] Bei den Untersuchungen der Hexacyanoferrate war reversibles Verhalten in der Voltammetrie zu beobachten, aber leider nie ein reversibles Verhalten in der Potentiometrie. Subtrahiert man also die Standardpotentiale des potentiometrischen Systems von dem des voltammetrischen Systems, erhält man das Standardpotential des Elektronentransfers.…”

“…Subtrahiert man also die Standardpotentiale des potentiometrischen Systems von dem des voltammetrischen Systems, erhält man das Standardpotential des Elektronentransfers. Ein zweiter glücklicher Umstand führte zu den in Abbildung 4g ezeigten Goldkomplexen [13] und zu Pseudopeptiden, [23] Bei den Untersuchungen der Hexacyanoferrate war reversibles Verhalten in der Voltammetrie zu beobachten, aber leider nie ein reversibles Verhalten in der Potentiometrie. Sonst wären Tr ennungen der Freien Enthalpien des Elektronen-und Ionentransfers sicher schon früher mçglich gewesen.…”

Cation and anion electrochemically assisted solid-state transformations of malachite green

“…26,27 Recently, Scholz et al 28 studied the difference between the voltammetric and potentiometric responses of a tungsten bronze electrode, concluding that while in voltammetry, ion insertion/release phenomena under potentiometric ion transfer conditions parallels that occurring in glass electrodes. 29,30 As a result, a separation between the electronic and ionic contributions to the Gibbs energy can be achieved, 28,31,32 prompting the experimental determination of thermochemical properties for single-ion solvation using membrane-modified liquid-liquid interfaces, 33 micro/nanoholes, 34 and triple-phase boundary measurements at microdroplets immobilized on electrode surfaces, 35 among other procedures.…”