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The fully computer-controlled user-dedicated small-angle scattering facility JUSIFA was set up for general use at the DORIS Synchrotron Radiation Source in DESY (Hamburg). This beamline is especially designed for anomalous scattering studies of anisotropic samples in materials science and enables ASAXS studies to be undertaken on the length scale 0.5 to 100 nm in an energy range of 4.5 to 35 keV.

Anomalous small‐angle X‐ray scattering (ASAXS) of synchrotron radiation with X‐ray energies near the Pt‐L3 X‐ray absorption edge was used to examine the size distribution of nanometer‐sized catalyst particles in porous electrodes for electrocatalytic applications. Carbon‐supported platinum electrocatalysts with 5–80 wt% Pt were studied in situ in an electrochemical cell with a 1 M sulfuric acid electrolyte. The anodic oxidation was found to shift the particle size distribution from a mean size of 1.7 nm in the reduced state to 2.1 nm for a 10 wt% Pt/C catalyst. From the size increase, one can infer the formation of oxide shells at the particle surfaces with layer thicknesses of about 1 nm.

We have synthesized nanostructured metal/organic networks by cross-linking preformed aluminum-organic-stabilized Pt nanoparticles in solution with organic spacer molecules. The protonolytic cross-linking mechanism presented makes use of reactive aluminum methyl groups at the surface of the particles. The particles and their networks have been characterized by electron microscopy and IR spectroscopy. For the structural characterization of the hybrids, anomalous small-angle X-ray scattering (ASAXS) was applied.

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