Fabrication and characterization of bulk nanoporous copper by dealloying Al-Cu alloy slices

Bulk NPC (nanoporous copper) were fabricated by dealloying xAl(100−x)Cu (x = 60, 70 at.%) alloy slices in NaOH solutions (10, 20 and 30 wt.%) under free corrosion conditions. The results show that Al-Cu alloy slices can be completely dealloyed. The synergetic dealloying of Al2Cu and AlCu results in the formation of uniform NPC with small-sized channels. The dealloying of α-Al and Al2Cu plays an important role in the formation of NPC with two kinds of structures of both small-sized uniform ligaments-channels and hierarchical skeleton-like (large-sized channels with highly porous walls) structure, and these two structures form layer-cake structure.