Το work with title Synthesis and characterization of ceria-based nano-structured materials: structure-activity relationships by Lykaki Maria is licensed under Creative Commons Attribution 4.0 International
Bibliographic Citation
Maria Lykaki, "Synthesis and characterization of ceria-based nano-structured materials: structure-activity relationships", Doctoral Dissertation, School of Production Engineering and Management, Technical University of Crete, Chania, Greece, 2021
https://doi.org/10.26233/heallink.tuc.89653
The rational design and development of highly-active and cost-efficient catalysts for energy and environmental applications constitutes the main research pillar in the area of heterogeneous catalysis. In this perspective, the present thesis aims at the fine-tuning of noble metal (NMs)-free metal oxide catalysts, such as ceria-based transition metal catalysts (MxOy/CeO2, where M stands for Cu, Co, Fe, Ni) by means of advanced synthetic and/or promotional routes. It was clearly revealed that the adjustment of size, shape and electronic state of ceria-based metal oxides (MOs) can exert a profound influence on the reactivity of metal sites as well as on metal-support interfacial activity, offering extremely active and stable materials for various applications, such as CO oxidation, N2O decomposition and CO2 hydrogenation to value-added products.Through the present thesis, the pivotal role of support morphology and surface promotion on the solid state properties, metal-support interactions and in turn, on the catalytic performance of ceria-based mixed oxides was unambiguously revealed. More importantly, the fine-tuning of size, shape and electronic state can notably affect not only the reactivity of metal sites but also the interfacial activity (e.g., through the formation of oxygen vacancies and the facilitation of redox interplay between the metal and the support) offering a synergistic contribution towards the development of highly active composites. Through the proposed optimization approach extremely active and cost-efficient catalytic materials were obtained for CO oxidation, N2O decomposition and CO2 hydrogenation reactions, being among the most active reported so far in open literature. The general optimization framework followed in the present thesis can provide the design principles towards the development of earth-abundant metal oxides for various energy and environmental applications paving also the way for the decrease of noble metals content in NMs-based catalysts.