Three-dimensional bicontinuous nanoporous materials by vapor phase dealloying

Abstract

Three-dimensional bicontinuous open (3DBO) nanoporosity has been recognized as an important nanoarchitecture for catalysis, sensing, and energy storage. Dealloying, i.e., selectively removing a component from an alloy, is an efficient way to fabricate nanoporous materials. However, current electrochemical and liquid-metal dealloying methods can only be applied to a limited number of alloys and usually require an etching process with chemical waste. Here, we report a green and universal approach, vapor-phase dealloying, to fabricate nanoporous materials by utilizing the vapor pressure difference between constituent elements in an alloy to selectively remove a component with a high partial vapor pressure for 3DBO nanoporosity. We demonstrate that extensive elements, regardless of chemical activity, can be fabricated as nanoporous materials with tunable pore sizes. Importantly, the evaporated components can be fully recovered. This environmentally friendly dealloying method paves a way to fabricate 3DBO nanoporous materials for a wide range of structural and functional applications.

Phase-field investigation of the coarsening of porous structures by surface diffusion

“…This processing technique presents the advantage of being applicable to a wide range of metals including titanium [13], iron [14], niobium [15], and tantalum [16,17], or semiconductors such as silicon [18]. Also, comparable porous structures have been obtained from vapor phase dealloying that relies on the low partial pressure of one of the component of the alloy to trigger selective dissolution [19,20].…”

“…* pierre-antoine.geslin@insa-lyon.fr Despite the differences between these processing routes, the resulting materials present very similar microstructures that evolve at least partly through surface diffusion as demonstrated by the activation energy of the coarsening process and by the expected power-law evolution of the ligament size [13,[20][21][22]. This coarsening process is important to control and limit as much as possible because it leads to a severe decrease of the specific surface area and therefore to a drop of materials properties.…”

Architected porous metals in electrochemical energy storage

“…Sponge replication method can be viewed as a variation of the previous methods in which metallic powder slurry is impregnated into polymeric foam followed by pyrolysis of polymer and post-sintering [6]. Dealloying, a corrosion process in which one or several components of an alloy are dissolved, is a powerful method of fabrication of metal foams and sponges capable of producing micro-, nano-and hierarchical (micro-nano) pores [13,27,28].…”

Chemical Dealloying Synthesis of CuS Nanowire-on-Nanoplate Network as Anode Materials for Li-Ion Batteries

“…Dealloying as an ancient and popular technique to fabricate nanoporous metals [15,16] has been recently extended into a new method for synthesizing nanostructured metal oxides/sulfides [17][18][19] with different morphologies. Morphology controllable CuS nanoplates were successfully acquired by Zhu et al [19,20] through the simple and low-cost dealloying method.…”