Secondary ion mass spectrometry and X-ray photoelectron spectroscopy investigation on chemical vapor deposited CeO2-ZrO2-TiO2 thin films

Mixed CeO2-ZrO2 systems have attracted a widespread interest for their use in three way catalysts (TWC) technology for automotive exhaust conversion into non-toxic products. In this work, CeO2-ZrO2 thin films were deposited via Chemical Vapor Deposition, in order to obtain nanoscale materials with a high surface-to-volume ratio, having a deep control of system properties. The addition of a buffer TiO2 thin film was also investigated. Cordierite was chosen as substrate, being the usual refractory material for catalytic mufflers. The multilayers were characterized by Scanning Electron Microscopy, X-ray Photoelectron Spectroscopy and Secondary Ion Mass Spectrometry. In particular, the combination of SIMS and XPS allowed to investigate both surface and in-depth chemical composition, studying also films intermixing phenomena induced by annealing processes.