Preparation of nanoporous copper foil by chemical dealloying from electro-deposited CuZn alloy

Nanoporous metals have been widely used in recent years for energy storage, catalysis and sensors due to their special structure and functional properties. One useful way to produce nanoporous metal is the dealloying approach. In this paper, the authors used seignette salt (NaKC4H4O6) as a coordinating agent to electrodeposit CuZn alloys under alkaline conditions, and then prepared the nanoporous copper foil through chemical corrosion dealloying. In order to study the electrochemical behaviour of the CuZn alloy electrodeposition process, cyclic voltammetry testing was carried out. The results show that the CuZn alloy electrodeposition is an irreversible reaction under diffusion control and follows the initial three-dimensional nucleation mechanism. The nucleation process is dominated by continuous nucleation. In addition, the surface crystal grains and zinc content increase with the increase of current density. After dealloying the CuZn alloy, the existence of nanoporous structure was confirmed by SEM (scanning electron microscopy). Under the optimum technical conditions, the pore size of the nanoporous copper foil is about 200–800 nm with thickness of the porous layer 2–5 μm. It is believed that this research offers an alternative pathway for designing nanoporous copper foil materials and related high performance for numerous applications.