Vibrational lifetimes of surface hydroxyl groups of zeolites by picosecond IR pulses

✍ Scribed by Jun Kubota; Motohiro Furuki; Yasumasa Goto; Junko Kondo; Akihide Wada; Kazunari Domen; Chiaki Hirose

• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 342 KB
• Volume: 204
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(93)90008-o

✦ Synopsis

Vibrational lifetimes of the surface hydroxyl groups of zeolites (Y-type and mordenite) were measured in real time by pumpprobe absorption spectroscopy using picosecond IR pulses. The relaxation lifetimes of the OH (II= I ) groups of Y-type zeolites which give the OH stretching bands at 3625 and 3540 cm-' were 180 k 12 and 63 + 14 ps, respectively. The influence ofthe microstructure of zeolites on the lifetime is discussed. For the surface OH groups of mordenite, the decay time of the transient hot band absorption at 3457 cm-' (v=2t 1) was also measured by pumping the fundamental band at 3608 cm-' to be 154 t 18 ps, which agreed with 161 k I8 ps obtained from the bleaching experiment of the fundamental band.