Q: What initially drew you to the APS?

Rachel: I was first introduced to the APS during graduate school, when I joined a research group that was already conducting experiments there. Initially, that work drew me in, and I quickly began designing my own projects around what was possible with X-rays at the APS.

Seeing the range of experiments that could be done, and how powerful the facility was as a research tool, made a strong impression on me. I completed my PhD at the University of Illinois, which is about two hours from the APS, so it was relatively easy to travel to the facility and gain experience there.

Over time, I realized that this was a community I wanted to stay connected to. My interest in continuing to work with X-rays and synchrotron-based techniques ultimately led me to pursue postdoctoral research at Argonne and to become involved with the APS user community through the UEC.

Q: Can you describe the research you’ve conducted at the APS? 

Rachel: My research at the APS focuses on understanding how light interacts with matter, particularly in systems relevant to photocatalysis. I study how light-driven processes can activate chemical reactions such as CO₂ reduction, water splitting, and bond formation, with applications ranging from energy to pharmaceuticals and agrochemistry.

In these experiments, we excite photocatalysts with optical laser light and then use time-resolved X-ray measurements to track how the system evolves over extremely short timescales. This allows us to observe transient structural and electronic changes that govern reactivity but are difficult to capture with other techniques.

I’ve conducted experiments across several APS beamlines, including earlier work at Sectors 7 and 11 and, more recently, at Sector 25, working closely with the time-resolved research group. I’ve also participated in studies using bending magnet beamlines to explore how changes in molecular or framework structure influence chemical reactivity.

Q: What role did the APS play in enabling or advancing your work? 

Rachel: The APS has been critical in advancing my research, particularly for time-resolved experiments. Following the APS upgrade, changes to the X-ray pulse structure, combined with new data-collection approaches developed by the time-resolved research group, have made it possible to gather far more detailed information than previously available.

These capabilities allow us to observe processes that I haven’t been able to study elsewhere, and that are not readily accessible at other synchrotrons. With the same experimental effort, we can collect much larger and more informative datasets, fundamentally changing the questions we can ask.

In practice, this means we can directly connect ultrafast structural changes to chemical reactivity, providing insight that would be extremely difficult to obtain without APS-specific capabilities.

Q: Has anything unexpected come out of your work with the APS, either in your results or in the process itself?

Rachel: One of the most striking aspects of working at the APS has been seeing how beamline teams design, build, and troubleshoot experimental setups. Being closely connected to the time-resolved research group has given me insight into the effort required to make complex experiments work reliably.

I’ve also been impressed by how seriously user feedback is taken. Beamline scientists are highly invested in improving setups and workflows, and that collaborative approach has been a valuable part of the process.

While this may not be unexpected in hindsight, it has been especially rewarding to experience firsthand how user input directly shapes experimental capabilities at the APS.

Q: What impact has your research at the APS had on your work so far? What are you excited about exploring next?

Rachel: The availability of time-resolved user programs at the APS has had a significant impact on the field. These experiments are complex, but the APS provides a relatively straightforward environment compared to other facilities, which has encouraged more researchers to pursue time-resolved studies.

As a result, scientists from around the world are using APS beamlines to investigate a wide range of systems, including nanoparticles, catalytic materials, and other light-driven processes. In many cases, experiments that were once considered impractical at a synchrotron have become feasible.

Looking ahead, I’m excited to see how far we can push these capabilities. The combination of flexible beamlines, advanced instrumentation, and the freedom to build custom setups continues to open new directions for experiments that challenge conventional expectations of what synchrotron-based research can do.