Self-combustion Ni and Co-based perovskites as catalyst precursors for ammonia decomposition. Effect of Ce and Mg doping

LaCo1-xNixO3 perovskites have been synthesized by self-combustion, characterized, and examined as catalyst precursors for the COx-free hydrogen production from catalytic ammonia decomposition at low temperatures. The influence of the cobalt content as well as the addition of two dopant in different...

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Detalles Bibliográficos
Autores: Pinzón García, Marina, Sánchez-Sánchez, A., Romero Izquierdo, Amaya, Osa Puebla, Ana Raquel de la, Sánchez Paredes, Paula
Tipo de recurso: artículo
Fecha de publicación:2022
País:España
Institución:Universidad de Castilla-La Mancha
Repositorio:RUIdeRA. Repositorio Institucional de la UCLM
OAI Identifier:oai:ruidera.uclm.es:10578/31191
Acceso en línea:https://hdl.handle.net/10578/31191
Access Level:acceso abierto
Palabra clave:Ammonia decomposition
Hydrogen production
Perovskites
Nickel
Ceria
Magnesia
Descomposición del amoníaco
Producción de hidrógeno
Perovskitas
Níquel
Descripción
Sumario:LaCo1-xNixO3 perovskites have been synthesized by self-combustion, characterized, and examined as catalyst precursors for the COx-free hydrogen production from catalytic ammonia decomposition at low temperatures. The influence of the cobalt content as well as the addition of two dopant in different amount was studied and optimized. Small Ni crystallite size and high total basic sites were found to remarkably enhance the catalytic activity. Moreover, bimetallic perovskites generated cobalt/nickel in higher size, higher impurities and lower active sites than pure nickel perovskite, which decreased the ammonia conversion. On the other hand, the addition of dopant in adequate amount over pure Ni perovskite (La0.1A0.9NiO3; A = Ce or Mg) generated catalyst with low nickel crystallite size and high basicity delivering superior catalytic performance. Catalysts were demonstrated to be stable for at least 40 h. In fact, 96 % and 98 % ammonia conversion were achieved at low temperature (400 °C), when La0.1Ce0.9NiO3 and La0.1Mg0.9NiO3 were employed, resulting from the synergic effect between La-Ce and Ni-Mg-La. Presenting the Mg-doped perovskite the highest catalytic activity at the mild temperature of 350 °C. This study provides new insight in designing diverse catalyst precursors to develop economic and efficient catalysts to achieve high ammonia conversion (high hydrogen production) at low temperature and enhance the ammonia perspective as hydrogen carrier toward the ‘hydrogen economy’.