Compositional Mapping of Poisoning Elements in Automobile Three-Way Catalytic Converters by Using Laser-Induced Breakdown Spectrometry

Abstract

The use of laser-induced breakdown spectrometry (LIBS) for generating two-dimensional (2D) multielemental distribution maps of poisoning agents in automobile three-way catalysts (TWCs) is discussed. A complete in-depth analysis of P, Zn, and Pb at different locations along the central channel of a used 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 these metals—i.e., Pt, Pd, and Ce—are also presented. The 2D maps provide a fast, useful, and intuitive tool to visualize the selective distribution of poisoning elements in a used TWC. This study may help explain the deterioration processes of a catalyst with a lifetime of about 30 000 km.