Activation of molecular oxygen over binuclear iron centers in Al-rich *BEA zeolite

Here, we present the unique redox properties of distant binuclear iron centers in Al-rich *BEA zeolite in O2 splitting and CH4 oxidation. Al-rich *BEA was obtained via a template-free synthesis procedure guaranteeing low-defected structure and a high fraction of Al-pairs enabling stabilization of binuclear iron centers. By employment of a multispectroscopic in-situ approach (Mo & BULL;ssbauer and X-ray absorption) the formation of active oxygen over binuclear iron centers in Al-rich *BEA was confirmed and subsequent CH4 oxidation was studied. Spontaneous release of the reaction products to the gas stream, representing a significant advantage of the studied system, was proved by the results of in-situ FTIR and mass spectrometry. This is the first experimental proof of the formation of fully-functioned binuclear iron centers (able to split O2, stabilize active oxygen forms, and subsequently oxidize CH4) in zeolite of *BEA topology.

Automated summary

In this study, the unique redox properties of distant binuclear iron centers in Al-rich *BEA zeolite in O2 splitting and CH4 oxidation were presented. The synthesis of Al-rich *BEA zeolite without a template ensured a low-defect structure and a high fraction of Al-pairs, stabilizing the binuclear iron centers. The formation of active oxygen over binuclear iron centers in Al-rich *BEA was confirmed using a multispectroscopic in-situ approach, and subsequent CH4 oxidation was studied. Spontaneous release of the reaction products to the gas stream was proven, demonstrating the significant advantage of the studied system. This is the first experimental proof of the formation of fully-functioned binuclear iron centers in zeolite of *BEA topology.