TY - JOUR
T1 - The observation of nanometer-sized entities in sulphided Mo-based catalysts on various supports
AU - Kooyman, P.J.
AU - Hensen, E.J.M.
AU - Jong, de, A.M.
AU - Niemantsverdriet, J.W.
AU - Veen, van, J.A.R.
PY - 2001
Y1 - 2001
N2 - The progressive sulfidation of molybdenum-based hydrotreating model catalysts is studied using HRTEM and XPS. The catalysts are sulfided quasi in situ and prepd. for TEM measurements in a glovebox. Subsequently, a specially developed vacuum-transfer specimen holder is used for transfer to the TEM. Using this procedure, a previously unknown feature is obsd. in the catalysts. Apart from the well-known slab-like structure of bulk molybdenum disulfide, nanometer-sized spherical entities of molybdenum sulfide or oxysulfide are obsd. For a series of model Co-Mo/silica catalysts, these \"spots\" predominantly occur after mild sulfidation procedures. At higher sulfidation temps., these spots exist next to the slabs of MoS2-like material. Comparison with practical molybdenum-based hydrotreating catalysts shows that these, too, can contain spots next to or instead of slabs, depending on precursor prepn. and sulfidation procedures. [on SciFinder (R)]
AB - The progressive sulfidation of molybdenum-based hydrotreating model catalysts is studied using HRTEM and XPS. The catalysts are sulfided quasi in situ and prepd. for TEM measurements in a glovebox. Subsequently, a specially developed vacuum-transfer specimen holder is used for transfer to the TEM. Using this procedure, a previously unknown feature is obsd. in the catalysts. Apart from the well-known slab-like structure of bulk molybdenum disulfide, nanometer-sized spherical entities of molybdenum sulfide or oxysulfide are obsd. For a series of model Co-Mo/silica catalysts, these \"spots\" predominantly occur after mild sulfidation procedures. At higher sulfidation temps., these spots exist next to the slabs of MoS2-like material. Comparison with practical molybdenum-based hydrotreating catalysts shows that these, too, can contain spots next to or instead of slabs, depending on precursor prepn. and sulfidation procedures. [on SciFinder (R)]
U2 - 10.1023/A:1016632130625
DO - 10.1023/A:1016632130625
M3 - Article
SN - 1011-372X
VL - 74
SP - 49
EP - 53
JO - Catalysis Letters
JF - Catalysis Letters
IS - 1-2
ER -