A process for the electrochemical production of an iron oxide/hydroxide-containing conducting polymer composite by one of the following processes: Process I, which comprises the following steps: a) providing a conducting polymer layer, optionally performing partial irreversible electrochemical oxidation (overoxidation) on the conducting polymer layer; b) electrochemical reduction of the conducting polymer layer, optionally in a solution containing ferrate ions; c) contacting the reduced conducting polymer layer with an aqueous solution of ferrate ions; d) optionally repeating steps b) and c); e) optionally separating the composite from the electrode used in the electrochemical reactions, and, if desired, drying the composite; or Process II, which comprises the following steps: a) providing a conducting polymer layer, optionally electrochemically reducing the conducting polymer layer; b) contacting the conducting polymer layer with an aqueous solution of ferrate ions; c) electrochemical oxidation of the conducting polymer layer in an aqueous solution of ferrate ions; d) electrochemical reduction of the oxidized conducting polymer layer in an aqueous solution of ferrate ions; e) optionally repeating steps c) and d); f) optionally separating the composite from the electrode used in the electrochemical reactions, and, if desired, drying the composite. Process I, which comprises the following steps: a) providing a conducting polymer layer, optionally performing partial irreversible electrochemical oxidation (overoxidation) on the conducting polymer layer; b) electrochemical reduction of the conducting polymer layer, optionally in a solution containing ferrate ions; c) contacting the reduced conducting polymer layer with an aqueous solution of ferrate ions; d) optionally repeating steps b) and c); e) optionally separating the composite from the electrode used in the electrochemical reactions, and, if desired, drying the composite; or a) providing a conducting polymer layer, optionally performing partial irreversible electrochemical oxidation (overoxidation) on the conducting polymer layer; b) electrochemical reduction of the conducting polymer layer, optionally in a solution containing ferrate ions; c) contacting the reduced conducting polymer layer with an aqueous solution of ferrate ions; d) optionally repeating steps b) and c); e) optionally separating the composite from the electrode used in the electrochemical reactions, and, if desired, drying the composite; or Process II, which comprises the following steps: a) providing a conducting polymer layer, optionally electrochemically reducing the conducting polymer layer; b) contacting the conducting polymer layer with an aqueous solution of ferrate ions; c) electrochemical oxidation of the conducting polymer layer in an aqueous solution of ferrate ions; d) electrochemical reduction of the oxidized conducting polymer layer in an aqueous solution of ferrate ions; e) optionally repeating steps c) and d); f) optionally separating the composite from the electrode used in the electrochemical reactions, and, if desired, drying the composite. a) providing a conducting polymer layer, optionally electrochemically reducing the conducting polymer layer; b) contacting the conducting polymer layer with an aqueous solution of ferrate ions; c) electrochemical oxidation of the conducting polymer layer in an aqueous solution of ferrate ions; d) electrochemical reduction of the oxidized conducting polymer layer in an aqueous solution of ferrate ions; e) optionally repeating steps c) and d); f) optionally separating the composite from the electrode used in the electrochemical reactions, and, if desired, drying the composite.