The Physical Chemistry Division of the American Chemical Society has named Xiaoji Xu as the winner of the prestigious 2025 Richard Van Duyne Early Career Award in Experimental Physical Chemistry.

The award recognizes outstanding contributions in experimental physical chemistry by a young investigator. Xu will accept the award and present an award lecture at the 2025 Fall ACS National Meeting.

Xu’s research focuses on developing infrared (IR) spectroscopic and imaging tools based on the atomic force microscope (AFM) to measure and visualize chemical compositions and their response to light at an incredibly small scale—less than 10 nanometers, or about 1/10,000th the width of a human hair. His group has developed the peak force infrared microscopy as a new type of photothermal AFM-IR imaging tool. His recent inventions include the time-domain AFM-based two-dimensional infrared spectroscopy (AFM-2DIR) and pulsed force Kelvin probe force microscopy that is a new type of Kelvin probe force microscopy that gives nanometric spatial resolution on surface electrical properties.

With his tools, Xu is particularly interested in how molecules, materials, and microscopic structures are organized and interact. His research covers a range of systems, including plastics (polymers), tiny airborne particles (aerosols), light-responsive materials (polaritonic materials), photovoltaics, and biological samples. By exploring these interactions, he aims to deepen our understanding of nanoscale phenomena and their potential applications towards new functions of molecules and materials.

"I am proud of the work my colleagues pursue and this award is a deserved recognition for Xiaoji's research,” said Robert Flowers, Herbert J. & Ann L. Siegel Dean of the College of Arts and Sciences and Danser Distinguished Faculty Chair of chemistry. ”New tools enable scientific discoveries, and he has been leading the way in his field since he came to Lehigh. By developing cutting-edge techniques, he is revolutionizing chemical analysis at the nanoscale. The quality and importance of his work is frequently evidenced by the national and international recognition he is receiving."

Prior to joining the Lehigh faculty, Xu was a postdoctoral fellow at the University of Toronto. He received his B.S. from Peking University and Ph.D. from The University of British Columbia. He has published more than 60 peer-reviewed articles and received several granted patents on AFM-based infrared microscopy. He was selected as a Beckman Young Investigator in 2018 and Sloan Research Fellow in 2020. He is also a recipient of the NSF CAREER award in 2019 and Camille Dreyfus Teacher-Scholar Award in 2021. He is a senior member of the National Academy of Inventors.

Xu also serves as advisor to PhD student Qing Xie, who received a 2024 ACS PHYS Graduate Student Award for her work involving broadband infrared nano-spectroscopy.