ARROYO CAIRE, JAVIER, Duran-Uribe, Edgar S. , LARA ANGULO, MAYRA ANABEL, DIAZ PEREZ, MANUEL ANTONIO, Sepulveda-Escribano, Antonio , SERRANO RUIZ, JUAN CARLOS
No
Int. J. Hydrog. Energy
Article
Científica
1
1
29/06/2026
1,78877E+12
2-s2.0-105040736766
The design of ammonia synthesis catalysts that are both scalable and kinetically efficient remains a major challenge for decarbonizing chemical production. Here, we report a series of Ru/CexLa1-xOy catalysts synthesized via a simple impregnation method, using only air-stable rare-earth oxides. Among them, the optimum Ru/ Ce0.5La0.5Oy catalyst displays an ultra-finely dispersed Ru phase supported on a Ce-La solid solution with a high density of oxygen vacancies. Under mild conditions (400 degrees C, 0.1 MPa), this system delivers a remarkably low apparent activation energy (34.1 kJ mol-1), outperforming many state-of-the-art more complex hydride or intermetallic catalysts. Additionally, the catalyst exhibited a strongly positive dependence of the reaction rate on pressure, making it particularly well suited for operation at moderate pressures (2-3 MPa) typically delivered by PEM electrolyzers for hydrogen. These findings position Ru/Ce0.5La0.5Oy as a rare example of a simple, stable catalyst combining the favorable kinetic behavior of more complex Ru systems with the scalability and robustness demanded by renewable-based decentralized ammonia synthesis.
Ammonia synthesis; Ru/CexLa1-xOy; Oxygen vacancies; Dispersion