Solid state electrochemical DeNOx—An overview

The literature on direct electrochemical reduction of NOx in a solid state cell has been reviewed. It is shown that the reduction of nitric oxide either occurs on the electrode or on the electrolyte if F-centers are formed. It is also shown that some oxide based electrodes has a high apparent selectivity towards the reduction of nitric oxide in a net oxidizing atmosphere. The activity and apparent selectivity of oxide based electrodes is strongly dependent on the composition of the oxide. The selectivity of noble metal based electrodes is generally very low. However, coating of noble metal based electrodes can give current efficiencies of up to 20% even in the presence of large amounts of oxygen.

Figure optionsDownload as PowerPoint slideResearch highlights▶ Solid state electrochemical DeNOx is reviewed. ▶ Noble metals show only little use as cathodes for electrochemical DeNOx. ▶ Noble metals with coatings show promising use as cathodes for electrochemical DeNOx. ▶ Some oxides also show promising use as cathodes for electrochemical DeNOx.