EFFECT OF TI MODIFIED ALUMINA SURFACE ON DISPERSION OF SUPPORTED Mo

Abstract

Abstract: High angle annular dark field–scanning transmission electron microscopy (HAADF-STEM) and high resolution electron microscopy (HREM) techniques were used to study the size of MoO3 and the average length and layer numbers of MoS2 slabs after sulfidation, respectively, in Mo/Al2O3, Mo/6%TiO2-Al2O3 and Mo/12%TiO2-Al2O3 catalysts. It is found that TiO2 modification makes the size of MoO3 particle increases from 0.7 nm to 1 nm in oxidized catalyst, the average layer numbers of MoS2 increases from 1.1 to 1.2 layers in sulfided catalyst, while the length increases from 3 nm to 3.2 nm. These phenomena could be well explained by the theory of metal-support interaction (MSI). Based on above results, the transformation from MoO3 particles to MoS2 slabs was investigated according to the change of Mo atom numbers in each crystal.

Key words: TiO2 modification, Al2O3 surface, high angle annular dark field–scanning transmission electron microscopy, high resolution electron microscopy, metal dispersion

CLC Number:

References

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