Snapshots of a working catalyst: possibilities and limitations of in situ spectroscopy in the field of heterogeneous catalysis

Abstract

Probing events taking place in a heterogeneous catalyst under reaction conditions has attracted a lot of attention in recent years. It requires the development of characterization techniques and the construction of in situ spectroscopic–reaction cells, which allow the identification of reaction intermediates and active sites in a working catalyst. The ultimate goals are the development of quantitative structure/composition–activity/selectivity relationships and the gathering of fundamental insight in short- and/or long-term deactivation mechanisms of heterogeneous catalysts. The use of in situ infrared, Raman, UV–VIS, electron paramagnetic resonance, nuclear magnetic resonance, X-ray absorption and Mössbauer spectroscopy; the construction of valuable spectroscopic-reaction cells and the possibilities and limitations to monitor real time catalytic events are reviewed. Several case studies describing the use of in situ spectroscopy in catalysis research are discussed.