This 2025 Physical Sciences and Engineering Early Investigator Named Award recipient is using advanced spectroscopy methods to understand the structural and electronic properties of catalysts and chemical interfaces at the nanoscale.
Each year, the Physical Sciences and Engineering (PSE) directorate at the U.S. Department of Energy's (DOE) Argonne National Laboratory recognizes exceptional early-career researchers breaking into their fields with the PSE Early Investigator Named Awards. In 2025, the lab announced six awardees would be receiving support in the form of funding and mentorship to conduct groundbreaking research aligned with Argonne's strategic mission.
One member of the 2025 cohort is Gengnan Li, an assistant scientist in the Nanoscience and Technology division at Argonne. Li, who uses a combination of theoretical and experimental approaches to study catalysis and energy applications, will be working under the guidance of Nathan Guisinger, scientist at the Center for Nanoscale Materials (CNM), on a proposal titled, "Real-Time Monitoring of Interfacial Dynamics Using Integrated Near-Ambient-Pressure X-ray Photoelectron Spectroscopy Platform." This platform -- though it holds promise for understanding surface-sensitive chemistries under conditions that closely mimic reaction environments -- currently lacks tools and processes for real-time, efficient and accurate analyses.
"The dynamic and collaborative environment at Argonne not only broadens my scientific perspective, but also allows me to contribute directly to advancing research that has real-world impact." -- Gengnan Li, Argonne assistant scientist
Here, Li discusses her research and other work she supports at Argonne.
Q: What role do you play at the lab?
A: I primarily work on understanding and developing materials at the nanoscale through combined theoretical and experimental approaches for energy applications. At CNM, which is a DOE Office of Science user facility, I also work with users to investigate structural and electronic properties of materials using multimodal in situ techniques.
Q: What initiatives or projects are you most excited about being involved in at Argonne?
A: The project I am most excited about involves developing advanced characterization capabilities to investigate the dynamic nature of surface chemical species. In catalytic reactions, surface atoms are highly active, and their electronic structures vary under operating conditions. At CNM, state-of-the-art characterization techniques enable us to capture these changes and gain deeper insights into the fundamental properties of materials. This understanding will, in turn, guide the design of next-generation materials with optimized performance and efficiency.
Q: Can you talk a bit about the research you're conducting for your proposal for which you received the 2025 PSE Early Investigator Named Award?
A: Near-ambient pressure X-ray photoelectron spectroscopy (NAP-XPS) represents a substantial advancement in surface science, bridging the boundary between ultrahigh vacuum conditions and real-world environments. The new NAP-XPS at the CNM allows real-time observation of dynamic surface changes under elevated pressures (up to 30 millibars) over short time scales (milliseconds), making it indispensable for studying surface interactions with gases, liquids or plasma. This capability enables researchers to capture and analyze how surface chemistry, electronic states and molecular structures evolve in response to varying environmental factors. While NAP-XPS has been successfully applied to study gas-solid systems, its application to liquid-solid interfaces presents multifaceted challenges, arising from both the inherent limitations of the technique and the complexities involved in studying these interfaces under realistic conditions. In the proposed project, we aim to make the advanced capabilities of NAP-XPS accessible to a broader range of researchers by developing user-friendly interfaces, comprehensive training platforms and streamlined workflows that allow scientists from various disciplines to utilize the technique for gas-liquid-solid interface studies.
Q: What do you like most about your job?
A: At CNM, I most enjoy the opportunity to collaborate with a diverse range of researchers and support cutting-edge scientific projects. The dynamic and collaborative environment at Argonne not only broadens my scientific perspective, but also allows me to contribute directly to advancing research that has real-world impact.
Q: How does your work support the lab's mission?
A: My work supports the lab's mission by advancing our understanding of materials and processes through developing and applying advanced characterization techniques. The obtained insights guide the design of next-generation catalysts and functional materials. By collaborating with users and researchers across different disciplines, my work will contribute to Argonne's broader goal of enabling scientific discovery and innovation that address national and global challenges.
Q: What do you enjoy doing outside of work?
A: Outside of work, I enjoy spending time caring for plants and exploring different aspects of gardening. Tending to my indoor and outdoor plants helps me relax and stay connected to nature.
Q: What other sorts of career or professional development opportunities has Argonne provided?
A: Argonne has provided a wide range of career and professional development opportunities at the group, division and laboratory-wide levels. I have benefited from mentorship and collaborations that helped me strengthen my skills.
Q: What encouraged you to get involved in the scientific discipline you are in?
A: I got interested in this field because I have always been curious about how materials behave at the nanoscale and how we can tune their properties at the atomic level to make them perform better.