Nanoporous Metal Foams

Abstract

Nanoporous metal foams (NMFs) have been a long sought-after class of materials in the quest for high-surface-area conductive and catalytic materials. Herein we present an overview of newly developed synthetic strategies for producing NMFs along with an in-depth discussion of combustion synthesis as a versatile and scalable approach for the preparation of nanoporous, nanostructured metal foams. Current applications of NMFs prepared using combustion synthesis are also presented including hydrogen storage and catalysis.

Understanding the synergistic effects of gold bimetallic catalysts

“…Thereby, the activity for the low-temperature CO oxidation can be rather high in spite of the very large Au-Ag particles. This model can also be used to explain the excellent activity of nanoporous gold (NPG) reported by several groups [84][85][86]. Since NPG is obtained by dissolving the Ag component in the bulk AuAg metal alloy materials, the residual Ag, even in a very small amount, will greatly affect the activity of NPG [87].…”

Nanoporous Gold Electrodes and Their Applications in Analytical Chemistry

“…Nanoporous electrodes have also be entermed "microporous" or "mesoporous" electrodes [18,[32][33][34][35][36] as this is the IUPAC definition of a material with 0.2-2 nm and 2-50 nm pores, respectively. They may also be referred to as nanoporous foams [37], particularly when they are in a monolithic form. In this paper, the focus will be on nanoporous gold made through dealloying, either chemically or electrochemically [9].…”

“…Nanoporous gold consists of a bicontinuous nanostructure with pores and ligaments in the nanometer size range [9]. In many respects, they are a conducting version of a silica aerogel: an open, foam-like 3D structure of nanometer sized pores accessible to species in solution or the vapor phase [37]. A representative SEM image of surface of a nanoporous gold electrode made in our lab by dealloying 12 K white gold leaf and capturing it on a gold slide is shown in Figure 2.…”

Template-based fabrication of nanoporous metals

“…Offering low density, high specific (i.e., density-normalized) surface area, and high specific strength while retaining many characteristics of bulk metals, this burgeoning class of metallic materials has garnered considerable research interest. [1][2][3][4][5][6] In addition to use as lightweight materials, nanoporous metals also have potential applications in a diverse array of technologies, such as optical metamaterial, 7 catalysis, 8,9 energy storage, 10 gas storage and filtration, 11 electromagnetic sensing, 12 and high-coercivity magnets. 2 With the continued realization of their unique properties, nanoporous metals are positioned to drastically invigorate the applicability of metals in new highperformance applications.…”