Combining Resonant Soft X-Ray Scattering (RSoXS) and In-Situ Liquid Flow for Nanoparticle Characterization at the Advanced Light Source (ALS): An Overview of the Technique, Recent Advancements, and Applications

Resonant soft X-ray scattering (RSoXS) is a powerful tool for chemically and orientationally resolved characterization of nano-to-mesoscale complex molecular materials. In the last few years, in-situ microfluidic capabilities have garnered increased attention and use from researchers studying various systems, from polymeric micelles to 2D catalytic surfaces. A challenging aspect of using soft X-rays for dynamic studies is their low penetration depths through the air, thus requiring high vacuum environments, which make sample preparations more complex and add further limitations/requirements to all in-chamber instrumentation. As such, the development of vacuum-compatible in-situ sample environments has been a critical requirement for applying the power of soft X-rays to novel systems that cannot be exposed to vacuum. Significant steps forward have been made at both the ALS and NSLS-II RSoXS beamlines to develop these needed sample environments, such as static and flow liquid/gas/electrochemical microfluidic cells. This talk will provide an overview of the technique and recent advancements. It will also highlight a few of the most recent discoveries using the RSoXS multimodal microfluidic instrument at the ALS.