About this Abstract |
Meeting |
MS&T22: Materials Science & Technology
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Symposium
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Synthesis, Characterization, Modeling and Applications of Functional Porous Materials
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Presentation Title |
Energetic Insights into Encapsulation of Molybdenum Oxide and Carbide Particles in Zeolite Y |
Author(s) |
Xianghui Zhang, Margaret E Reece, Andrew C. Strzelecki, Cody Cockreham, Vitaliy G. Goncharov, Houqian Li, Kyungmin Yim, Jinsoo Kim, Junming Sun, Hui Sun, Baodong Wang, Xiaofeng Guo, Hongwu Xu, Su Ha, Yong Wang, Di Wu |
On-Site Speaker (Planned) |
Di Wu |
Abstract Scope |
Encapsulation of transition metal oxides and carbides in zeolites leads to effective catalytic particles and clusters for methane conversion and biomass upgrading. Here we report our recent experimental studies on the thermodynamics of molybdenum trioxide (MoO3) and molybdenum carbide (Mo2C) formation under confinement in zeolite Y (FAU) Si/Al ratio varies employing high-temperature oxide melt solution calorimetry. Specifically, at the same Mo loading, the enthalpies of formation for MoO3/FAU and Mo2C/FAU from constituent oxides and carbides become less endothermic as the Si/Al ratio increases. Encapsulation of Mo2C is energetically more favorable compared with the confinement of MoO3 in zeolite Y by ∼30 kJ/mol per tetrahedron unit. Unlike MoO3 which has high redox transition flexibility to achieve lower energetic states, it is the strong bonding at the Mo2C–FAU interfaces that compensate for the energetic deficiency to achieve highly dispersed Mo2C particles. Well-dispersed Mo2C was also synthesized on Ni-Mo2C/FAU for methane-steam reforming. |