Electrochemical deposition of gold at liquid–liquid interfaces studied by thin organic film-modified electrodes

Abstract

The unique physico-chemical properties of gold nanoparticles portrayed in their chemical stability, the sizedependent electrochemistry, and the unusual optical properties make them suitable modifiers of various surfaces used in the fields of optical devices, electronics, and biosensors. In this work we present two different methods to obtain metallic gold nanoparticles at a liquid-liquid interface, and to control their growth by adjusting the experimental conditions. Decamethylferrocene (DMFC), used as an oxidizable compound dissolved in an organic solvent that is spread as a thin film on the surface of graphite electrode, serves as a redox partner to exchange electrons across the liquid-liquid interface with the other redox counter-partner

Interfacial Synthesis of Nylon‐6,6 and Its Modification with Silver‐Based Nanoparticles at the Electrified Liquid‐Liquid Interface

“…[13] In this respect, metallic nanoparticles can be formed within the interface originating from the cationic precursor reduction (initially dissolved in the aqueous phase) by the organic phase soluble electron donor (usually ferrocene and its derivatives). [14][15][16][17] Another example is electrochemically controlled interfacial polymerization either derived from the electron [18][19][20][21] or ion transfer reaction. [22] Sol-gel processing in a biphasic environment can also be studied or controlled using electroanalytical techniques.…”

“…The in situ modification is derived from the interfacial ion or electron transfer triggering the reaction(s) whose product(s) resided within the interfacial region in a form of solid/soft deposits [13] . In this respect, metallic nanoparticles can be formed within the interface originating from the cationic precursor reduction (initially dissolved in the aqueous phase) by the organic phase soluble electron donor (usually ferrocene and its derivatives) [14–17] . Another example is electrochemically controlled interfacial polymerization either derived from the electron [18–21] or ion transfer reaction [22] .…”

Assisted Ion Transfer at Organic Film-Modified Electrodes

“…Following the first experiments of Bard et al in which a microelectrode was covered with a film of an organic solvent, Anson et al , developed thin-film electrodes (TFE) in which pyrolytic graphite was modified with a thin film of a water-immiscible organic solvent containing a lipophilic redox probe. Thin-film electrodes have been broadly applied to study a variety of electrochemical phenomena ranging from ion and electron transfer kinetics across L|L interfaces, − biomimetic studies, − to preparation and electrochemical inspection of noble metal nanoparticles. , Following the advances of thin-film electrodes, a three-phase electrode (TPE) system has been developed, which appears in a variety of configurations, such as electrodes modified with randomly distributed microdroplets of redox-active organic liquids, or a paraffin-impregnated graphite electrode partly covered with a single droplet of an organic solvent containing a neutral lipophilic redox probe . Three-phase electrodes are extensively applied to study thermodynamics of ion transfers across the interface between water and a variety of solvents .…”

New techniques and devices for UV-Vis absorption spectroelectrochemistry

“…Posteriormente, gracias al desarrollo de los potenciostatos que permitían trabajar con cuatro electrodos realizado por Samec [26][27][28] , se consiguió solventar el problema existente de la caída óhmica en estos sistemas, lo que hizo posible la utilización de técnicas a potencial controlado como voltamperometría cíclica [29][30][31][32][33] , voltamperometría diferencial de pulso 34 , cronoamperometría 35 , polarografía 36,37 y espectroscopía de impedancia 38,39 que pudieron aportar mayor información sobre las ITIES. El estudio espectroeletroquímico de estos sistemas ha sido posible gracias a la evolución de estas técnicas y ha ayudado a lograr una mayor comprensión de las ITIES.…”

“…33.a shows the evolution of the spectra of 10 -3 M catechol in PBS during one amperometric spectroelectrochemistry experiment.One main absorption band is observed at 390 nm that yields an almost constant value of absorbance at the end of the experiment. A shoulder between 450 and 650 nm is observed in the last spectra of the experiment(Figure 4.33.a, inset).…”