Sandia Labs FY21 LDRD Annual Report

FY21 ANNUAL REPORT

Ultra-high-resolution electron scattering apparatus advances study of electron interactions with gas molecules and temporal evolution of plasmas. Electron scattering by atoms and molecules, a fundamental process occurring in a broad range of scientific disciplines, is integral to plasma properties. Plasmas impact a diverse field of technical applications critical to national security, and advances in understanding and modeling plasmas enable

faster development of associated technology. An ultra-high-resolution electron scattering apparatus, developed by leveraging Sandia’s expertise in ion/ electron imaging methods, enables the study of electron-scattering processes in gas phase molecules and provides a method for studying the temporal evolution of laser-initiated plasmas. The versatile capability developed through this LDRD project will be used by multiple sponsors in applied and fundamental fields to inform predictions of plasma physics, plasma- assisted chemistry, neutron generation, and arcing. (PI: Jonathan Frank)

Cross-section view of ultra-high-resolution electron scattering apparatus.

Novel capability will enable researchers to tackle ongoing questions of gas-surface chemistry. Energy efficient heterogeneous catalytic processes are key to energy applications. This LDRD project focused on developing an experimental method able to image the near-surface gas-phase with high spatial resolution. Combining the benefits of electron microscopy with selective laser ionization of important heterogeneous reaction products emitted from catalytic surfaces, this approach will provide for fundamental mechanistic insight into gas-surface chemical interaction and cooperative pathways.

Researchers can use this novel, cross-cutting tool to measure maps of gas-surface exchange as it depends on the local structure and composition of the surface, elucidating the combined effects of surface activity, gas-phase transport, and gas-phase reactivity. This will lead to a more predictive capability in heterogenous catalysis and have a significant impact in basic energy and science fields. (PI: Chris Kliewer) The development of a method for correlated operando surface/gas characterization provides a great sandbox for surface studies. Shown here is a low-energy electron microscopy image of a clean Iridium (111) surface.

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LABORATORY DIRECTED RESEARCH & DEVELOPMENT