In a method and device for separating components in a corona discharge zone an air stream containing water molecules is passed between at least one ionizing electrode and at least one non-ionizing electrode; and high voltage is applied to the electrodes to create a corona discharge zone consisting of a plasma region wherein ozone is formed and a dark region where predominantly hydrogen peroxide is formed. The air flow entering the corona discharge zone is divided into two separate air flows, a first of which passes through the corona discharge plasma region, and a second of which passes through the dark corona discharge region; and a negative pressure gradient is applied to the plasma region only so as to remove the ozone and thereby separate the ozone from the hydrogen peroxide.