Irreversible xenon insertion into a small-pore zeolite at moderate pressures and temperatures

Wednesday, 17 December 2014
Yongjae Lee1, Donghoon Seoung1, Yongmoon Lee1, Hyunchae Cynn2, Changyong Park3, Kwang-Yong Choi4, Douglas Blom5, William Evans2, Chi-Chang Kao6 and Thomas Vogt5, (1)Yonsei University, Seoul, South Korea, (2)Lawrence Livermore National Laboratory, Livermore, CA, United States, (3)Geophysical Laboratory, Washington Dc, DC, United States, (4)Chung-Ang University, Seoul, South Korea, (5)University of South Carolina, Columbia, SC, United States, (6)SLAC National Accelerator Laboratory, Menlo Park, CA, United States
Pressure drastically alters chemical and physical properties of materials and allows structural phase transitions and chemical reactions to occur that defy much of our understanding gained at ambient conditions. Particularly exciting is the high-pressure chemistry of Xenon, which is known to react with hydrogen and ice at high pressures, and form stable compounds under pressure. Here we show that Ag16Al16Si24O80·16H2O irreversibly inserts Xe into its micropores at 1.7 GPa and 250 °C while Ag+ reduces to metallic Ag and possibly oxidizes to Ag2+. In contrast to Krypton, Xenon is retained within the pores of this zeolite after pressure release and requires heat to desorb. This irreversible insertion and trapping of Xenon in Ag-natrolite at moderate conditions sheds new light on chemical reactions that could account for a Xenon deficiency relative to Argon observed in terrestrial and Martian atmospheres.