Electrochemical performance of electrocatalysts. (IMAGE)
Caption
The NO3−RR performance of the (FeCoNiCu)Ox electrocatalyst was studied under different reduction potentials. The (FeCoNiCu)Ox electrocatalyst demonstrates a high FENH3 of over 90% in the wide potential range of 0 to −0.4 V vs. RHE. However, the rNH3 of the (FeCoNiCu)Ox is not as competitive compared to other oxide electrocatalysts reported in previous literatures. TEM and SEM images reveal particle agglomeration, which could affect the dispersion of active components. Previous studies have reported that incorporating CeO2 as a support in catalysts improves the uniform dispersion of active components and significantly increases the active surface area of the catalysts. Moreover, Ce has a much larger atomic radius than the other elements (Fe, Co, Ni and Cu) and thus Ce cannot incorporate the crystal structure of (FeCoNiCu)Ox even by the rapid Joule-heating method. Accordingly, a (FeCoNiCu)Ox/CeO2 composite catalyst was further successfully synthesized.
The electrochemical active surface area (ECSA) of the electrocatalysts was evaluated by double layer capacitance obtained from cyclic voltammetry. The ECSA of (FeCoNiCu)Ox/CeO2 is double that of both CeO2 and (FeCoNiCu)Ox, indicating that the addition of CeO2 improves the active surface area of (FeCoNiCu)Ox/CeO2. This finding was also supported by the specific surface area results obtained from the nitrogen adsorption/desorption method. Eventually, the (FeCoNiCu)Ox/CeO2 electrocatalyst exhibits superior high FENH3 and rNH3 at low overpotential, surpassing the majority of oxide electrocatalysts reported in previous literatures.
Credit
©Science China Press
Usage Restrictions
Use with credit.
License
Original content