(622g) In Situ/Operando Reaction Cells: Limitations and Opportunities in the UV-Vis and IR Characterization of Catalysts

In situ and operando spectroscopic characterization of catalysts is without a doubt a powerful tool to explore the nature of species that may be involved in a heterogeneously catalyzed catalytic cycle. In combination with methodologies to discriminate passive and active species, it can inform researchers on the presence of spectator and true reaction intermediate species. As in situ and operando methodologies become more routine and progress towards the simultaneous collection of spectroscopic and kinetic data in the same reaction cell, more rigorous evaluation of data acquisition and analysis, such as that usually done in laboratory scale reactors, is required to reach meaningful conclusions and avoid the proliferation of flawed and falsified kinetic data.^{1, 2}

In this presentation, we will focus on the limitations of current reaction cells mainly used for UV-vis and IR spectroscopies in the study of intermediate reaction species and kinetics of catalyzed reactions. Several aspects such as flow dynamics and mass and heat transfer in these reaction cells as well as their applications to spectrokinetics will be discussed as they pertain to the understanding of heterogeneously catalyzed reactions.

References

1. Bravo-Suárez JJ, Srinivasan PD. Design characteristics of in situ and operando ultraviolet-visible and vibrational spectroscopic reaction cells for heterogeneous catalysis. Catal Rev- Sci Eng 2017: pp1-151, DOI: 110.1080/01614940.01612017.01360071.
2. Srinivasan PD, Nitz SR, Stephens KJ, Atchison E, Bravo-Suarez JJ. Modified Harrick reaction cell for in situ/operando fiber optics diffuse reflectance UV–visible spectroscopic characterization of catalysts. Appl Catal, A 2018, 561: 7-18.