Instrument Development: In Operando Capability for Benchtop X-ray Emission Spectroscopy

University Of Washington, Seattle WA

Investigators

Abstract

With support from the Chemical Measurement & Imaging program, and partial co-funding from the Chemical Catalysis program, Professors Seidler and Cossairt of the University of Washington are working to develop a new x-ray spectrometer to enable studies of chemical systems in special sample environments. Specifically, they are developing analysis tools for characterization of materials actively involved in chemical reactions, such as during the synthesis of fuels from simple and abundant starting chemical species like water and carbon dioxide. Their work will greatly expand access to x-ray spectrometry by providing alternatives to specialized, large-scale light sources known as synchrotrons. Significant educational benefits derive from creating a multidisciplinary environment for the students involved and by incorporating advanced x-ray spectroscopy into senior-level laboratory courses in both Physics and Chemistry at the University of Washington. X-ray absorption fine structure (XAFS) and high-resolution x-ray emission spectroscopy (XES) are two advanced x-ray spectroscopies that have high impact across chemistry, materials science, environmental science, geophysics, and several other fields. However, their range of application is constrained by their general reliance on synchrotron x-ray light sources. Professors Seidler and Cossairt are developing a new lab-based spectrometer and source that can easily couple to special sample environments, such as an electrocatalytic cell. By enabling operando XES in the laboratory, this will pave the way for real-time studies of element-specific electronic structure of reactants and intermediates in many different types of chemical reactions, without a need for synchrotron beamtime. Information gained from these operando studies will provide new insight into the nature of element speciation during electrocatalytic processes, providing deeper knowledge of the mechanisms by which fuel-forming reactions occur and how catalytic sites might be altered to improve reaction trajectories in the future. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.