(754c) Stanford Synchrotron Radiation Lightsource and the Consortium for Operando and Advanced Catalyst Characterization Via Electronic Spectroscopy and Structure

The use of synchrotron radiation sources for the in-situ and operando characterization of catalysts and other functional materials has proven to be essential to providing relevant detailed structural information (electronic and geometric). The diverse techniques available at such user facilities, including X-ray absorption spectroscopy, small- and wide-angle X-ray scattering, X-ray microscopy, and ambient pressure X-ray photoelectron spectroscopy, to name a few provide crucial information that cannot be obtained by other means.

At Stanford Synchrotron Radiation Lightsource (SSRL) at SLAC National Accelerator Laboratory we have initiated a program, the Consortium for Operando and Advanced Catalyst Characterization via Electronic Spectroscopy and Structure (Co-ACCESS). The goal of Co-ACCESS is to enable any catalysis researcher (whether they study heterogeneous, homogeneous, electro- or photo-catalysis) with an interest in the X-ray methods of catalyst characterization, with a focus on in-situ and operando, to be able to pursue those interests in an expedient manner, with minimal barrier to conducting the research. This program builds on the proven success of the Synchrotron Catalysis Consortium at NSLS [1] and the existing strengths of SSRL in materials and geological sciences.

Materials and Methods

We are in the process of creating a holistic suite of integrated in-situ and operando synchrotron-based catalytic reactors by: (i) fabricating a suite of user-accessible in-situ cells, (i) constructing automated feed delivery systems, (iii) coupled with on-line analytics. These experimental facilities are enhanced by investments and developments at SSRL, e.g. in data collection and data processing methods, and new beamlines, coupled with access to a wet chemistry laboratory, designed for catalysis studies, to allow the synthesis, proper handling, and activation of catalysts on-site. All of these activities are assisted by experienced staff.

Results and Discussion

The focus on this presentation will be on the capability development, with details provided on the infrastructure that is now available at SSRL for catalysis, and other functional materials, studies and a look forward to some of the capabilities under development. These capabilities will be illustrated by research focused on elucidating the structure of functioning catalysts. This research has been performed collaboratively with numerous research groups. (i) The development of safe and routine operations at high pressure, facilitating research in syngas chemistry for higher alcohol synthesis and Fisher-Tropsch catalysis [2]. (ii) The application of high-energy resolution fluorescence detection methods for determining the active site complex [3][4], (iii) The development of time-resolved studies via continuous scanning of the monochromator, and (iv) The use of multi-modal methods, including XRD/XAS and XAS/TXM in order to extract more in­for­ma­tion for a given sys­tem [4].

Significance

SSRL offers a growing suite of tech­niques and me­tho­do­lo­gies for in-situ/operando advanced catalyst, and other functional materials, cha­rac­te­ri­za­tion. These techniques are driving new catalyst and materials dis­coveries by de­ter­mi­ning the structure res­ponsible for the ac­tivity, and vice-versa, the need to understand catalyst activity is also driving new ex­pe­ri­ments at SSRL.

Co-ACCESS, is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences.

References

1. SCC website, https://you.stonybrook.edu/scc2/, last accessed 23-Oct-2018.
2. Hoffman, A.S., Singh, J.A., Bent, S.F., and Bare, S.R. Synchr. Rad. (2018) 25 https://doi.org/10.1107/S1600577518013942
3. Hoffman, A.S., Sokaras, D., Zhang, S., Debefve, L.M., Fang, C.-Y., Gallo, A., Kroll, T., Dixon, D.A., Bare, S.R., Gates, B.C., Chemistry -A European Journal 23 1-10 (2017).
4. Hoffman, A.S., Azzam, S., Zhang, K., Xu, Y., Liu, Y., Bare, S.R., Simonetti, D.A., Reaction Chemistry & Engineering (2018) 3 668 – 675.