FTIR study of hydrogen and carbon monoxide adsorption on Pt/TiO{sub 2}, Pt/ZrO{sub 2}, and Pt/Al{sub 2}O{sub 3}

The Pt/TiO{sub 2}, Pt/ZrO{sub 2}, and Pt/Al{sub 2}O{sub 3} catalysts submitted to low-temperature reduction (LTR,200 C) and high-temperature reduction (HTR, 500 C) and exposed to hydrogen and carbon monoxide at room temperature were studied by infrared spectroscopy. There is a strong loss of transmission in the entire infrared spectra on Pt/TiO{sub 2} after its exposure to hydrogen, which is related to the reducibility of the support. A typical SMSI behavior (strong metal-support interaction), such as the decrease in carbon monoxide adsorption capacity, was detected on Pt/TiO{sub 2} and Pt/ZrO{sub 2} after exposure to hydrogen, even for the catalysts submitted to LTR treatment. Also a carbonyl band shift to lower wavenumber was observed on LTR-treated Pt/TiO{sub 2}, Pt/ZrO{sub 2}, and Pt/Al{sub 2}O{sub 3} after exposure to hydrogen. The authors interpreted this SMSI behavior as an electronic rather than morphological effect, which was induced by the presence of hydrogen spillover.