Yoshida, K, Shiju, N R, Brown, D.R., Boyes, E D and Gai, P L (2010) Double aberration-corrected TEM/STEM of tungstated zirconia nanocatalysts for the synthesis of paracetamol. Journal of Physics: Conference Series, 241 (1). 012035. ISSN 1742-6596Metadata only available from this repository.
We report highly active tungstated zirconia nanocatalysts for the synthesis of paracetamol by Beckmann rearrangement of 4-hydroxyacetophenone oxime. Double aberration-corrected (2AC)-TEM/STEM studies were performed in a JEOL 2200FS FEG TEM/STEM at the 1 Angstrom (1 Å = 0.1 nanometer) level. Observations at close to zero defocus were carried out using the AC-TEM as well as AC-STEM including high angle annular dark field (HAADF) imaging, from the same areas of the catalyst crystallites. The studies from the same areas have revealed the location and the nanostructure of the polytungstate species (clusters) and the nanograins of zirconia. The AC (S)TEM was crucial to observe the nanostructure and location of polytungstate clusters on the zirconia grains. Polytungstate clusters as small as 0.5 nm have been identified using the HAADF-STEM. The nanostructures of the catalyst and the W surface density have been correlated with paracetamol reaction studies. The results demonstrate the nature of active sites and high activity of the tungstated zirconia nanocatalyst, which is an environmentally clean alternative to the current homogeneous process.
|Additional Information:||Originally presented at Electron Microscopy and Analysis Group Conference 2009 (EMAG 2009) 8–11 September 2009, University of Sheffield, UK|
|Subjects:||Q Science > Q Science (General)|
Q Science > QD Chemistry
|Schools:||School of Applied Sciences|
School of Applied Sciences > Materials and Catalysis Research Centre
|Depositing User:||Sharon Beastall|
|Date Deposited:||11 Nov 2010 11:55|
|Last Modified:||11 Nov 2010 11:55|
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