The invention relates to a method for producing a membrane and such membrane. The method comprises the steps of: —providing a container with electrolyte; —placing a structure in the container; and —providing at least two electrodes with a potential difference to achieve a plasma electrolytic oxidation on the structure. Preferably, the structure comprises a metallic structure, with the metallic structure chosen from the group of Titanium, Aluminum, Magnesium, Zirconium, Zinc and Niobium, and/or an alloy.