Local structure of Pb(II) ion catalysts anchored within zeolite cavities and their photocatalytic reactivity for the elimination of N2O.

The Pb2+/ZSM-5 catalyst was prepared by an ion-exchange method and its photocatalytic activity for the decomposition of N2O under UV irradiation was investigated. In-situ UV-Vis absorption spectroscopy and XAFS (XANES and FT-EXAFS) investigations revealed that the Pb2+ ions exist in a highly dispersed state within the pores of the zeolites. UV irradiation of the catalysts in the presence of N2O led to the photocatalytic decomposition of N2O into N2 at temperatures as low as 298K. The effective wavelength of the irradiated UV light indicated that the excited state of the Pb2+ ions included within the zeolite cavities plays a significant role in the photocatalytic decomposition of N2O molecules.