(53p) Ultrasensitive Probing of Local Electronic Structure in the Soft X-Ray Regime

We are interested in the applicability and potential transformative impact of ultra-sensitive soft x-ray spectroscopy to map out the local electronic structure of reactants, intermediates, and products in chemical reactions. There is a need to go beyond current limitations in detection technology that can measure below 10% of a monolayer and see reactants/intermediates/products below 10mM in solution, which is close to current detection limitations.

We have recently commissioned a transition edge sensor (TES) based spectrometer at Stanford Synchrotron Radiation Laboratory (SSRL) that has the ability to explore new paradigms in soft x-ray spectroscopy, achieving sensitivity of sub-mMol concentrations in aqueous/organic solvents, sub-percent sensitivity for monolayer films immersed in a solvent, solid matrix, or high-pressure gas, and sensitivity to concentrations <1019/cm3 for defects and dopants in condensed phase samples.

We will demonstrate the ability of our TES based setup to probe carbon and nitrogen (e.g. CO2 and N2) dissolved in aqueous solutions, nitrogen detection below 1% of a monolayer, as well as preliminary results from gas-phase catalytic reduction. The prospects for soft x-ray spectroscopy to follow chemical reactions at complimentary timescales under realistic conditions will be discussed.