Catalysis lies at the heart of modern chemical and energy industries, enabling over 85% of industrial processes and contributing to more than 20% of global GDP. By lowering activation energies and offering selective reaction pathways, catalysts facilitate the transformation of raw materials into valuable chemicals, fuels, and pharmaceuticals. Despite its widespread application, catalysis remains one of the most complex and least understood areas of science. Key challenges include identifying true active sites under operating conditions, understanding dynamic structural and electronic changes during reactions, and controlling selectivity in multi-step transformations. These questions are critical for addressing global energy and environmental challenges, such as carbon dioxide utilization, green hydrogen production, and sustainable chemical manufacturing. Synchrotron-radiation-based methods uniquely advance catalysis science by delivering element-specific, surface- and time-resolved insight under realistic conditions. X-ray absorption spectroscopy (XAS, including XANES/EXAFS) tracks oxidation states, coordination numbers, and metal–ligand distances of active centers operando, revealing dynamic restructuring, ligand effects, and charge transfer during turnover. Ambient-pressure X-ray photoelectron spectroscopy (AP-XPS) probes surface composition, chemical states, adsorbates, and work-function shifts under near-realistic gas pressures, mapping reaction intermediates and identifying spectator species. Synchrotron infrared and Raman microspectroscopies (including SINS and tip-enhanced variants) resolve adsorbate vibrational fingerprints on specific facets or sites, linking surface coverage to kinetics. Grazing-incidence small- and wide-angle X-ray scattering (GI-SAXS/WAXS) monitor nanoparticle size, morphology, and phase transitions, while X-ray diffraction (including micro/nanobeam and pair-distribution function analysis) captures crystallographic changes and short-range order in amorphous or single-atom catalysts. Coherent and time-resolved techniques (e.g., pump-probe XAS, XPCS) reveal sub-millisecond dynamics, defect migration, and sintering pathways. Tomographic and ptychographic imaging quantify 3D architectures and transport heterogeneities in porous catalyst bodies, correlating structure with diffusion and deactivation patterns. Together, these multimodal, multiscale measurements enable direct identification of true active sites, operando reaction networks, and deactivation mechanisms; constrain microkinetic models with spectroscopic observables; and guide rational design-tuning support interactions, alloy composition, particle size/shape, and promoter/poison effects-thereby accelerating discovery of more active, selective, and stable catalytic materials.
As typical cases, Bao’s team employed synchrotron vacuum ultraviolet photoionization mass spectrometry (SVUV-PIMS) in Hefei Light Source (HLS) to identify the reaction intermediates in syngas-to-olefins conversion over ZnCrOx–zeolite bifunctional catalysts, elucidated the reaction pathway of ketene, and received the First Prize of the State Natural Science Award in 2020.[1] Developing acid-stable electrocatalysts for CO2 electroreduction is crucial for addressing energy and environmental challenges. Xia and co-workers employed operando synchrotron infrared and soft X-ray absorption spectroscopies to capture the structural evolution and electronic-state changes of active sites on a regenerated-lead catalyst during CO2 reduction across a wide pH range, providing key spectroscopic evidence for its acid-stable mechanism.[2] Tang's group successfully resolved the spatial separation mechanism of photogenerated charge carriers in intramolecular heterojunctions using in-situ irradiation soft X-ray absorption spectroscopy from HLS, achieving efficient conversion of methane into high-value chemicals.[3]
In the future, Hefei Light Source will collaborate with Hefei Advanced Light Facility (HALF), which has micro focus and world leading coherence, to leverage its different advantages for studying reaction tracking of interest in catalytic science applications, as well as studying the structure and electronic behavior of metal/non-metal species, which is expected to have a significant impact.
[1] Chen, Yuxiang, et al. Visualization of the active sites of zinc–chromium oxides and the CO/H2 activation mechanism in direct syngas conversion. Journal of the American Chemical Society 146.3 (2024): 1887-1893.
[2] Fang, Wensheng, et al. Durable CO2 conversion in the proton-exchange membrane system. Nature 626.7997 (2024): 86-91.
[3] Xie, Jijia, et al. Methane oxidation to ethanol by a molecular junction photocatalyst. Nature 639.8054 (2025): 368-374.