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

Abstract 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) Pt 3+ (CO) 2 dicarbonyls (2211 and 2175 cm −1 ), which are decomposed without producing monocarbonyls; (ii) Pt 2+ (CO) 2 (2165 and 2150 cm −1 ), decomposed via Pt 2+ –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.