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.