A series of studies were carried out in a variety of locations in Europe and North America on fresh and road-aged automotive catalysts. Platinum L3 and L2 edge X-ray absorption spectroscopy (XAS) was used alongside detailed laboratory based characterisation. X-ray absorption near edge structure (XANES) was found not sufficient to determine the nature of Pt species present in multi-component catalysts. Therefore detailed analysis of the extended X-ray absorption fine structure (EXAFS) was performed at the Pt L3 and L2 edges and this revealed mainly oxidic species to be present in the fresh catalysts, while metallic and bimetallic components were the dominant species in the road aged catalysts. Taken together, with the addition of Cl K-edge XANES analysis, it is concluded that no environmentally significant quantities of chloroplatinate species were present in the fresh or road-aged samples.
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