Heterogeneously Catalyzed Oxidation Reactions Using ... - CHEC

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CHAPTER 6
Figure 6‐1: Characteristic XRD pattern of the newly synthesized STA‐12(Co) MOF compared to STA‐12(Ni) [36]
in the as‐prepared state.
The structure of STA‐12(Co) was refined by the Rietveld method, using the GSAS suite of programs
[44], against laboratory powder X‐ray diffraction data (Fe Kα1, λ = 1.930642 Å). The structure of as‐
prepared STA‐12(Ni) was used as the starting model, with the cell derived from Le Bail fitting.
Positions of physisorbed water molecules were retained from STA‐12(Ni) and the reduced amount of
physisorbed water accounted for by changes in the occupancies of water sites. The final profile fit
shows good agreement with the observed diffraction pattern indicating STA‐12(Co) to be
isostructural (Figure 6‐2) with STA‐12(Ni).
The porosity of STA‐12(Co) was confirmed by N2 adsorption at 77 K on dehydrated samples of
STA‐12(Co). Samples were activated at 140 °C for 180 minutes and found to have a pore volume of
0.10 cm 3 g ‐1 (at p/p0 = 0.4). Synthesis and the characterization of the MOF material was done by
Michael T. Wahrmby and Paul A. Wright from the University of St. Andrews (UK).
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