Improvement of stability and reduction of energy consumption for Ti-based MnO electrode by Ce and carbon black co-incorporation in electrochemical degradation of ammonia nitrogen.

Ti-based electrode coated with MnO catalytic layer has presented superior electrochemical activity for degradation of organic pollution in wastewater, however, the industrial application of Ti-based MnO electrode is limited by the poor stability of the electrode. In this study, the novel Ti-based MnO electrodes co-incorporated with rare earth (Ce) and conductive carbon black (C) were prepared by spraying-calcination method. The Ti/Ce:MnO-C electrode, with uniform and integrated surface and enhanced Mn(IV) content by C and Ce co-incorporation, could completely remove ammonia nitrogen (NH-N) with N as the main product. The cell potential and energy consumption of Ti/Ce:MnO-C electrode during the electrochemical process was significantly reduced compared with Ti/MnO electrode, which mainly originated from the enhanced electrochemical activity and reduced charge transfer resistance by Ce and C co-incorporation. The accelerated lifetime tests in sulfuric acid showed that the actual service lifetime of Ti/Ce:MnO-C was ca. 25 times that of Ti/MnO, which demonstrated the significantly promoted stability of MnO-based electrode by Ce and C co-incorporation.