| AVS 62nd International Symposium & Exhibition | |
| In-Situ Spectroscopy and Microscopy Focus Topic | Monday Sessions |
| Session IS+AS+SS-MoM |
| Session: | Fundamental Studies of Surface Chemistry of Single Crystal and Nanomaterials under Reaction Conditions |
| Presenter: | Lena Trotochaud, Lawrence Berkeley National Laboratory (LBNL) |
| Authors: | L. Trotochaud, Lawrence Berkeley National Laboratory (LBNL) A.R. Head, Lawrence Berkeley National Laboratory (LBNL) Y. Yu, University of Maryland O. Karslioglu, LBNL M. Hartl, LBNL B. Eichhorn, University of Maryland H. Bluhm, LBNL |
| Correspondent: | Click to Email |
Filtration systems for absorption and decomposition of chemical warfare agents (CWAs) are the first line of defense against exposure to these toxic compounds. Composite materials (such as ASZM-TEDA) commonly used in filtration systems consist of high-surface-area carbon supports impregnated with various metals and metal oxides. Despite decades of work to develop highly effective and versatile filtration materials with long-term usability, little is known about the mechanisms of CWA degradation by material surfaces and catalyst deactivation and poisoning, in part due to the challenges involved with spectroscopic characterization of catalyst surfaces under operating conditions. Enabling the rational design of more advanced filtration and decomposition materials for broad-spectrum protection against CWAs and other toxic industrial compounds requires a sophisticated understanding of the chemical mechanisms behind CWA sorption and degradation on the molecular scale.
We will present the surface spectroscopic study of metallic and oxidized Cu(111) single crystal surfaces for catalytic decomposition of dimethyl methylphosphonate (DMMP), a CWA simulant. Ambient-pressure X-ray photoelectron spectroscopy (APXPS) enables examination of these surfaces during DMMP adsorption and decomposition. Initial experiments indicate that adsorption of DMMP on Cu(111) is observed at pressures as low as 1 × 10-7 Torr, and degradation of DMMP is observed at this pressure and higher (60 mTorr) at room temperature. Possible mechanisms of DMMP degradation and deactivation of the surface will also be discussed.