In Situ UV-Vis-NIR Absorption Spectroscopy and Catalysis
Max L Bols1, Jing Ma2, Fatima Rammal2
1Laboratory for Chemical Technology (LCT), University of Ghent, Technologiepark Zwijnaarde 125, 9052 Ghent, Belgium.
Chemical Reviews
|February 26, 2024
Summary
In situ UV-vis-NIR absorption spectroscopy is a powerful tool for understanding catalysis, enabling detailed mechanistic and kinetic studies across various catalyst types and reaction systems.
Area of Science:
- Catalysis
- Spectroscopy
- Materials Science
Background:
- In situ UV-vis-NIR absorption spectroscopy is crucial for characterizing catalytic processes.
- Understanding reaction mechanisms, kinetics, and structural properties requires advanced spectroscopic techniques.
Purpose of the Study:
- To review the application of in situ UV-vis-NIR absorption spectroscopy in catalysis.
- To highlight experimental techniques for mechanistic and kinetic studies.
- To demonstrate its utility in structural characterization of catalysts.
Main Methods:
- Utilizing stopped flow techniques, laser pulses, and experimental perturbations for in situ studies.
- Employing femto- and nanosecond resolved transient absorption measurements for photocatalysis.
- Combining UV-vis-NIR absorption with techniques like magnetic circular dichroism and resonance Raman spectroscopy.
Main Results:
- Spectroscopy tracks oxidation states, adsorptions, reactions, and support interactions in transition metal catalysts.
- In situ studies reveal insights into enzymatic, homogeneous, heterogeneous, and photocatalysis.
- Advanced analysis techniques overcome challenges like broad absorption bands for tracking complex reactions.
Conclusions:
- In situ UV-vis-NIR absorption spectroscopy provides valuable insights into catalyst characterization and mechanistic investigations.
- Its application can be expanded across diverse catalytic systems.
- Combining multiple spectroscopic methods enhances understanding of catalytic phenomena.
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