Electrodeposition of Nanoporous Gold Thin Films

Abstract

Nanoporous gold (NPG) films have attracted increasing interest over the last ten years due to their unique properties of high surface area, high selectivity, and electrochemical activity along with enhanced electrical conductivity, and chemical stability. A variety of fabrication techniques to synthesize NPG thin films have been explored so far including dealloying, templating, sputtering, self-assembling, and electrodeposition. In this review, the progress in the synthetic techniques over the last ten years to prepare porous gold films has been discussed with emphasis given on the technique of electrodeposition. Such films have wide-ranging applications in the fields of drug delivery, energy storage, heterogeneous catalysis, and optical sensing.

Highly Porous 3D Gold Enhances Sensitivity of Amperometric Biosensors Based on Oxidases and CuCe Nanoparticles

“…In particular, 2D and 3D materials with extra-large areas are the promising candidates for this aim [ 1 , 17 , 18 , 19 , 20 , 21 ]. A lot of synthetic methods for obtaining 3D materials have been described [ 10 , 24 , 25 , 26 , 27 , 28 , 29 , 30 ].…”

“…As a result, a pAu-modified electrode significantly increases the number of adsorption sites for enzymes and other biomolecules, thus improving electron transport in comparison with corresponding electrodes with nonporous surfaces. Thus, due to its intriguing properties, pAu is a very promising material for application in (bio)sensing, energy storage, diagnostic medicine, and drug delivery [ 14 , 19 , 21 , 22 , 23 , 24 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 ].…”

“…A variety of approaches to synthesize pAu have been reported in addition to methods of sputtering and self-assembling [ 17 , 27 , 41 ]. The pore size in pAu can be modulated from 5 up to 50 nm, depending on the type of synthesis protocol used [ 24 , 30 ].…”

“…Chemical and electrochemical dealloying were shown to lay a historical foundation for other methods [ 25 , 27 , 31 , 32 ]. This approach is appropriate for the fabrication of both monoporous (i.e., nanoporous or microporous) and hierarchically porous (i.e., possessing both microporosity and nanoporosity) metal structures with novel properties [ 23 , 24 , 43 ]. Hierarchical pores are highly desirable; the presence of larger-size pores enables the fast transport of the reactants, while the nanopores are responsible for providing a large surface area, thereby increasing the rate of electrochemical reactions.…”

“…High-surface-area pAu (such as films, membranes, or powders) could also be designed by the electrodeposition technique. This method of pAu preparation on a solid substrate has been extensively researched, and it has become the most popular method in recent years [ 17 , 23 , 24 ]. The advantages of electrodeposition strategies include: one-step fabrication of thin films directly on a substrate; relatively easy control of particle morphology, size, and density; uniform deposition and good stability; and the formation of hierarchically porous metal structures with novel properties.…”