Fabrication of Nanoporous Gold Film Electrodes with Ultrahigh Surface Area and Electrochemical Activity

Abstract

Nanoporous gold film (NPGF) electrode was fabricated by applying multicyclic potential scans on a polished gold electrode in an electrolyte composed of ZnCl 2 and benzyl alcohol. In the cathodic potential scan, Zn was first electrodeposited on the gold electrode surface, and Au-Zn alloy was then directly formed on the surface under an elevated temperature. In the subsequent anodic potential scan, dealloying of Zn took place, resulting in a nanostructured gold film. Furthermore, Zn was then electrodeposited onto the porous gold surface and a Au-Zn alloy was formed at the same time. Through controlling the parameters of cyclic voltammetry and cyclic times, we finally obtained a three-dimensional NPGF with nanopores. The resulting NPGF possessed ultrahigh roughness factor and surface area. Results showed that the electrochemical activity of the NPGF electrode was much higher than that of the polished gold electrode. We believe that the resulting NPGF electrode is promising in the fields of catalysis, sensors, and so on. Meanwhile, this multicyclic electrochemical alloying/dealloying method may be applied to fabricate other nanoporous metal films.

Nanoporous Gold Electrodes and Their Applications in Analytical Chemistry

“…Ligament sizes ranging from 10 nm-60 nm have been reported as have surface areas that are 200x greater than a planar gold substrate [68]. In a related method, the electrochemical alloying/dealloying process took placed on gold electrodes placed in an electrolyte prepared using ZnCl 2 and benzyl alcohol (BA) at elevated temperatures [173]. Figure 10 shows an SEM image of nanoporous gold fabricated by alloying/dealloying in the ZnCl 2 /BA at 120 ∘ C [173].…”

Nanoporous Gold Surface: An Efficient Platform for Hydrogen Evolution Reaction at Very Low Overpotential

“…[21][22][23][24] Currently, nanoporous gold films (NPGF) have attracted attention for their widespread application in catalysis and in the sensors field because of their higher surface area in comparison to bulk gold electrodes, allowing superior electron transfer rate between the electrode-electrolyte interface. 25,26 Such platforms have been mainly prepared by alloying/dealloying or template methods, where hazardous chemicals are mostly used. 27,28 Hence, it is really a challenging task to develop convenient and green methods to fabricate NPGF with high surface area.…”

Concurrent Electrocatalysis and Sensing of Hydrazine and Sulfite and Nitrite Ions using Electrodeposited Gold Nanostructure-Modified Electrode

“…The electrocatalytic property of Au nanoparticles (NPs) mainly depends on their preparation methods [19,20]. Previously, Maduraiveeran et al [15] reported the concurrent sensing of N 2 H 4 , SO 3 2-, and NO 2 -with a large decrease in the overpotentials using a colloidal Au NPs-modified electrode.…”