The present invention relates to an electrode comprising an electrically conductive substrate and a catalytically active layer, wherein the catalytically active layer is based on two catalytically active components and comprises iridium, ruthenium or titanium as metal oxide or mixed oxide or mixtures of the oxides, wherein the total content of ruthenium and/or iridium based on the sum of the elements iridium, ruthenium and titanium is at least 10 mol %, and wherein the electrode comprises at least one oxidic base layer which is applied to the electrically conductive substrate and is impermeable to aqueous electrolytes comprising NaCl and/or NaOH and/or HCl.