Fabrication and characterization of nanoporous copper through chemical dealloying of cold-rolled and annealed Mn–Cu alloy

Abstract

This study investigated the effects of the manufacturing process on the microstructure of nanoporous copper (NPC) produced using cold-rolled Mn-30 at.% Cu and Mn-40 at.% Cu precursor sheets. NPC was prepared by chemically dealloying these precursor sheets in a 4% HCl aqueous solution. The initial Mn-Cu alloys were homogenous solid solutions with good cold-rolling workability. After dealloying, Mn-30 at.% Cu and Mn-40 at.% Cu precursors formed nanoporous structures with ligament size of 122 ± 5 nm and 97 ± 4 nm, respectively. In addition, the annealing conditions of the precursors were strongly related to the formation of a bi-continuous nanoporous structure. This was attributed to the lower diffusivity of Mn atoms at 550 ℃ than that at 750 ℃, which resulted in the slower rearrangement of Cu atoms during the dealloying process. Additionally, NPC sheets derived from annealed Mn-30 at.% Cu precursors at different annealing temperatures under the same dealloying condition exhibited ligament sizes of 223 ± 9 nm and 149 ± 4 nm. These results indicate that the change in the annealing temperature of the precursor significantly refined the nanoporous structure.

Effect of Surface Microstructure on Joints Using Nanoporous Cu Sheet for Power Devices

“…Cu-based precursor alloys are generally fabricated by melt spinning method. However, our previous study revealed that the nanoporous Cu sheet by cold-rolled Mn-Cu precursor could achieve a homogeneous and large crack-free nanoporous structure using an adequate annealing process [8]. In this study, the bonding process using nanoporous Cu sheet formed from Mn-Cu precursor was investigated to achieve a Cu disk/Cu disk bonding without solvent and flux.…”

Dealloying of Pt1Bi2 intermetallic toward optimization of electrocatalysis on a Bi-continuous nanoporous core–shell structure

“…Nanocatalysts with bi-continuous nanoporous structures are used in a wide range of applications, including catalysis, energy storage, and sensing, due to their high effective surface area, high corrosion resistance, and electrical properties. [1][2][3][4] One effective approach to achieving open nanoporosity of nanomaterials is dealloying, which can be used to prepare materials that exhibit a flexible porous structure with a pore size and particle composition that can be conveniently adjusted. [5][6][7][8] The Pt-based nano dealloying process usually involves the dissolution of non-Pt metals and the diffusion of Pt atoms on the surface, thus forming a Pt-rich surface layer (shells) supported on an alloy core.…”