Revealing Fe speciation and its impact on catalytic activity in MFI and CHA zeolite structures during methane non-oxidative coupling by oper

Non-oxidative coupling of methane is a direct route for natural gas monetization. We have developed a series of Fe-doped zeolite catalysts and discovered that their catalytic performance highly depends on the Fe species confined in zeolites with different topologies (CHA and MFI). Herein, we propose operando HERFD-XANES/XES measurements by using a pulse reactor at ID26, which will help us elucidate the evolution of Fe species at a high temporal resolution during methane non-oxidative coupling process. We will perform a detailed qualitative and quantitative analysis of Fe speciation by using HERFD-XANES with a focus on the pre-edge features, and identify the specific ligands (C or O) linked to Fe-centers by XES. This information will allow us to directly link the structure and evolution of active sites to their catalytic activity under real reaction conditions and therefore will provide a comprehensive understanding of the catalyst activation and deactivation mechanisms.