jp034750h_si_003.mpg (656.66 kB)
Localization of Small Metal (Oxide) Particles in SBA-15 Using Bright-Field Electron Tomography
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posted on 2003-07-16, 00:00 authored by A. H. Janssen, C.-M. Yang, Y. Wang, F. Schüth, A. J. Koster, K. P. de JongSmall gold (5 nm) and zirconia (2−3 nm) particles inside the mesopores of SBA-15 were visualized with
bright-field electron tomography. Due to the ordered nature of the mesopores and the related diffraction
contrast present in the tilt series, the 3D-reconstruction is difficult to interpret. Unequivocal information has
been obtained, however, on the presence of the particles in certain pores, while others pores are empty. This
nonuniform distribution of particles over the mesopores explains the two-step desorption isotherm in nitrogen
physisorption experiments.