Catalysts are the core of heterogeneous catalytic reactions. Due to the complexity of catalytic reactions, humans have very limited knowledge of the active phases of the catalysts. The structure-performance relationship of the catalyst during the reaction is important for understanding the catalytic reaction process and improving the catalyst. The Operando technique can monitor the evolution of the catalyst structure in real time, detect the reaction products online and promote the rational design of industrial catalysts. Firstly, this paper introduces the development history of catalytic reaction and dynamic in-site characterization technique, and then describes the Operando Raman technique in Fischer-Tropsch synthesis (FTS) and CO2 hydrogenation combining with recent research progress. The application of typical catalytic reactions demonstrate the structural evolution process and structure-performance relationship of the catalyst under different pretreatment and precursor conditions. However, the temporal resolution and spatial resolution of the current Operand technique still need to be further improved. In addition, the Operando technique still has vast development potential in solid-liquid and gas-liquid catalytic reactions.

Operando technique; iron-based catalysts; structure-performance relationship; carbon dioxide hydrogenation; Fischer-Tropsch synthesis