The NiFe2O4-MgFe2O4 series as electrode materials for electrochemical reduction of NOx

摘要: Solid solutions of spinel-type oxides with the composition \(\rm Ni_{1-\mathit{x}}Mg_{\mathit{x}}Fe_2O_4\) (x = 0.0, 0.3, 0.5, 0.6, 1.0) were prepared glycine-nitrate combustion synthesis 0.6) and citric-acid 1.0). The used as electrode materials in a pseudo-three-electrode setup temperature range 400–600 °C. Cyclic voltammetry electrochemical impedance spectroscopy to characterize behavior 1% NO 10% O2. Measurements show that NiFe2O4 has relatively high cathodic activity both O2, whereas MgFe2O4 shows much higher compared was also measured cyclic NO2 different gas mixtures O2 at 300 400 Results activities (−0.6 V) are current ratios, \( I_{\rm{NO}_{\mathit{x}}+\rm{O_2}}/I_{\rm{O_2}}\), ranging from 10.1–167.7 maximum Dilatometry measurements performed on air up 1,000 °C, they showed Curie could be detected for all samples. Four-point DC resistivity elevated temperatures Ni0.4Mg0.6Fe2O4 highest conductivity, Ni0.7Mg0.3Fe2O4 have conductivity lower temperatures.