Compositional mapping of poisoning elements in automobile three-way catalytic converters by using laser-induced breakdown spectrometry

The use of laser-induced breakdown spectrometry (LIBS) for generating two-d imensional (2D) multielemental distribution maps of poisoning agents in aut omobile three-way catalysts (TWCs) is discussed. A complete in-depth analys is of P, Zn, and Pb at different locations along the central channel of a u sed TWC in the gas flow direction was performed. The distribution maps for the metals in charge of the catalytic action and for the stabilizer of thes e metals-i.e., Pt, Pd, and Ce-are also presented. The 2D maps provide a fas t, useful, and intuitive tool to visualize the selective distribution of po isoning elements in a used TWC, This study may help explain the deteriorati on processes of a catalyst with a lifetime of about 30 000 km.