Gold Nanofilm Redox Catalysis for Oxygen Reduction at Soft Interfaces

Abstract

The interfacial reduction of oxygen by a lipophilic electron donor, decamethylferrocene, dissolved in α,α,α-trifluorotoluene was catalyzed at a gold nanoparticle nanofilm modified water–oil interface. A recently developed microinjection technique was utilized to modify the interface reproducibly with the mirror-like gold nanoparticle nanofilm, while the oxidized electron donor species and the reduction product, hydrogen peroxide, were detected by ion transfer voltammetry and UV/vis spectroscopy, respectively. Metallization of the soft interface allowed the interfacial oxygen reduction reaction to proceed via an alternative mechanism with enhanced kinetics and at a significantly lower overpotential in comparison to a bare soft interface. Weaker lipophilic reductants, such as ferrocene, were capable of charging the interfacial gold nanoparticle nanofilm but did not have sufficient thermodynamic driving force to significantly elicit interfacial oxygen reduction.