Macro-/micro-coupling regulation of nanoporous metals via vapor phase alloying-dealloying

Abstract

Nanoporous metals with bicontinuous ligament-channel structure are of great importance in catalysis, electro-catalysis, actuation and energy storage and conversion. However, the intrinsic brittleness of nanoporous metals has always been the “Achilles heel” that impedes their practical applications. Utilizing the vapor pressure difference of metals, herein we propose a flexible and general vapor phase alloying (VPA)-dealloying strategy to fabricate nanoporous layers supported on the substrates with the same element. By adjusting the VPA time and temperature, the thickness and microstructure control over nanoporous layers can be realized by combining with diverse dealloying methods. Besides, various metals including Ag, Au, Cu, Co and Ni with different macro sizes and shapes can be fabricated into nanoporous structures through this method. More importantly, the greatly improved tensile ductility owing to the nanoporous layer-substrate structure and well enhanced catalytic performance for hydrogen evolution reaction of the as-fabricated nanoporous metals signify great potentials of the VPA-dealloying strategy for practical applications.