In the industrial production of chlorine, recently special electrodes have been introduced, which consume much less current than conventional systems. The method requires oxygen which is introduced into hot, highly concentrated sodium hydroxide solution, in which it is poorly soluble. It is still unclear how industrial current densities can be achieved under these conditions. Researchers from Bochum and Clausthal have gained new insight into the processes involving these types of electrodes, also referred to as oxygen-depolarised cathodes.