Pattern formation during electrochemical and liquid metal dealloying

Abstract

Abstract

Dealloyed nanoporous materials with interface-controlled behavior

“…The article by McCue et al 20 in this issue describes recent progress in our understanding of dealloying mechanisms based on the morphology of the dealloyed structures, providing considerable information on the transport processes involved in selective dissolution. McCue et al discuss experimental and state-of-the-art simulation approaches aimed at identifying atomic-scale processes and the driving forces for various forms of dealloying.…”

Dealloyed Nanoporous Gold Catalysts: From Macroscopic Foams to Nanoparticulate Architectures

“…For example, Au 0.23 Ag 0.77 alloy nanoparticles smaller than 10 nm transform into core‐shell nanoparticles each of which is composed of an alloy core and an Au shell (Figure A–2C), whereas Au 0.23 Ag 0.77 alloy nanoparticles larger than 20 nm evolve into spongy nanoparticles (Figure D–2F) under otherwise identical electrochemical dealloying conditions. Alloy nanoparticles substantially larger than ∼20 nm typically undergo nanoporosity‐evolving morphological changes involving both ligament pinch‐off and void bubble formation during percolation dealloying (Figure G), analogous to their macroscopic bulk counterparts with the same compositions. The percolation dealloying of alloy nanoparticles enables controlled introduction of nanoscale porosity to a large variety of substrate‐supported or free‐standing Au nanostructures (Figure H–2L) ,…”

“…[22] Alloy nanoparticles may undergo dealloying-driven structural transformations that are more versatile than those of their bulk and thin film counterparts displaying a planar surface to the electrolyte. For example, Au 0.23 Ag 0.77 alloy nanoparticles smaller than 10 nm transform into core-shell nanoparticles each of which is composed of an alloy core and an Au shell ( Figure 2G), [27][28] analogous to their macroscopic bulk counterparts with the same compositions. The percolation dealloying of alloy nanoparticles enables controlled introduction of nanoscale porosity to a large variety of substrate-supported or free-standing Au nanostructures ( Figure 2H-2L).…”

“…The percolation dealloying of alloy nanoparticles enables controlled introduction of nanoscale porosity to a large variety of substrate-supported or free-standing Au nanostructures ( Figure 2H-2L). [19,[28][29][30][31][32]…”

Nanoporous Copper-Nickel – Macroscopic bodies of a strong and deformable nanoporous base metal by dealloying

“…Macroporous bodies of more abundant and affordable metals are obtained by liquid metal dealloying. Macroporous titanium, niobium, or stainless steel have been demonstrated in this way [25][26][27][28]. Yet, dealloying in liquid metal is experimentally more onerous than aqueous dealloying.…”