FTIR spectroscopic study of CO adsorption on Pt-H-ZSM-5

This work reports the formation of some new non-classical carbonyls of platinum formed after CO adsorption on Pt-H-ZSM-5. These are: (i) Pt3+(CO)2 dicarbonyls (2211 and 2175 cm−1), which are decomposed without producing monocarbonyls; (ii) Pt2+(CO)2 (2165 and 2150 cm−1), decomposed via Pt2+-CO species (2113 cm−1); and (iii) Pt+(CO)3 complexes (2162, 2150 and 2110 cm−1) which easily loose one CO ligand even at room temperature being thus converted to Pt+(CO)2 (2120 and 2091 cm−1). The latter are thermally decomposed without producing monocarbonyls.