Rapid Synthesis of Nanoporous Zn Powder by Selective Etching of Al from Micrometer-Sized Zn–Al Powder Particles Produced by Gas Atomization and Its Application in Hydrogen Generation

The scalable synthesis of non-precious nanoporous metals, such as nanoporous zinc (NP-Zn), nanoporous iron (NP-Fe), and nanoporous aluminum (NP-Al), is crucial for large-scale production of hydrogen through the reaction between non-precious metals and water. The fabrication of bulk NP-Zn by selective removal of Al from sub-centimeter-sized arc-melted Zn-Al parent alloys through free corrosion dealloying usually takes a few days. Here, we demonstrate that this free corrosion dealloying process can be reduced from a few days to 4 min simply using micrometer-sized Zn-Al powder particles with nominal composition Zn