HAADF-STEM Study of Mo/V Distributions in Mo-V-Te-Ta-O M1 Phases and Their Correlations with Surface Reactivity
作者： Vadim V. Guliants , Albina Borisevich , Qian He , Jungwon Woo
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摘要: The MoVTeTaO M1 phases were prepared by conventional hydrothermal (HT) and microwave-assisted HT synthesis methods (MW) employing two different Ta precursors, ethoxide a custom-made oxalate complex. profile intensity analysis of the HAADF-STEM image oriented along [hk0] directions from surface to bulk region images indicated that chemical composition ab planes is very similar their in bulk. showed have significant impact on Mo/V distribution reactivity propane ammoxidation. Enhanced acrylonitrile (ACN) yield 1st order irreversible reaction rate constants for consumption, normalized estimated plane areas, correlated with increased V content proposed catalytic center (S2-S4-S4-S7-S7). These observations lend further support idea multiple VOx sites present may be responsible activity selectivity phase
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