Photo-enhanced selective conversion of ethane to ethene over single-site Mo-modified SAPO-34

Abstract

This study reveals photo-enhanced activity for selective conversion of ethane to ethene over single-site Mo-modified SAPO-34. Light irradiation significantly reduces the activation energy required for the conversion of ethane to ethene by approximately 47 kJ/mol. Combining structural analyses and theoretical calculations, we identify HO-Mo(V)=O as the active species responsible for the selective C–H cleavage of C₂H₆ in the manner of C₂H₅-O-Mo-O(2H). Photo-irradiation triggers the electron transition from the double-bond O to Mo, promoting C–H cleavage. Simultaneously, the photo-induced, electron-deficient, double-bond oxygen in O=Mo(V)-OH acts as the Lewis acid (LA) while the basic skeleton oxygen in Al-O-P of SAPO-34 serves as the Lewis base (LB), creating a frustrated Lewis pair (FLP). This cooperative interaction facilitates the breaking of C–H bonds and allows for more efficient C–H stretching, aided by the increased distance between LA and LB. The photo-assisted C–H activation enhances the overall formation efficiency of C₂H₄ over Mo-SAPO-34.