In a process of producing a porous layer of electrolytically depositable metal a support material (1) is immersed in an electrolytic medium (2) comprising ions of the metal and the metal is electrolytically deposited onto the support material (1) in the presence of an oxidising species which reacts with the metal to form a product which is reducible under the deposition conditions. In one form of process, a metal is deposited onto a support material (1) from an aqueous medium comprising ions of the metal, oxygen being introduced into the medium to pass in the vicinity of the support material. The process enables highly porous metal to be manufactured. The porous metal obtained is useful as catalytic material or as electrode material.
