Recent advances and opportunities in the use of synchrotron radiation-based FTIR technique (SR-FTIR) in catalytic studies

Synchrotron radiation-based Fourier transform infrared (SR-FTIR) spectroscopy has emerged as a powerful tool for the structural and mechanistic investigation of catalytic materials and reactions. This review highlights some of the most recent advances and opportunities offered by SR-FTIR in catalytic science, emphasizing two key applications: (i)in situ and operando IR microspectroscopy, and (ii) the characterization of catalyst vibrations in the far-infrared (FIR) region. The high brilliance and broad spectral range of synchrotron light enable diffraction-limited spatial resolution, superior signal-to-noise ratios, and access to low-frequency vibrational modes which are difficult to probe using conventional thermal sources. Representative studies are presented to illustrate the unique capabilities of SR-FTIR microspectroscopy in resolving spatial heterogeneities in catalyst particles, monitoring reaction intermediates in microreactors, and achieving sub-second temporal resolution. Additionally, the integration of SR-based nano-FTIR techniques opens new possibilities for nanoscale chemical imaging of catalytic sites. The review also surveys the growing use of FIR spectroscopy, particularly with synchrotron sources, for elucidating metal-ligand and framework vibrations in metal-organic frameworks (MOFs) and zeolite materials respectively, as well as structural modifications in metal oxide-based catalysts. Finally, current challenges and perspectives are outlined, highlining examples on multimodal approaches combining SR-FTIR with complementary synchrotron-based X-ray methods as well as future directions enabled by 4th generation synchrotrons.