Isolated Single‐Atom Ruthenium Anchored on Beta Zeolite as an Efficient Heterogeneous Catalyst for Styrene Epoxidation

Abstract Exploring high‐performance styrene epoxidation catalysts is of great significance. However, it still remains a challenge to synthesize heterogeneous catalysts that simultaneously possess excellent styrene activity and styrene oxide selectivity. Herein, we report a heterogeneous isolated single‐atom Ru supported on microporous Beta zeolite (Ru₁/Beta) catalyst fabricated by a wet impregnation method. We reveal that the extraframework AlOH groups on Beta zeolite are responsible for anchoring Ru species, which is determined by ²⁷Al MAS NMR analyses. The abundant AlOH on microporous Beta zeolite can lead to single‐atom ruthenium dispersion, thereby resulting in marked enhanced catalytic performance in styrene epoxidation than Ru cluster on Beta zeolite. The turnover frequency (TOF) value of Ru₁/Beta reaches 353 h⁻¹, 3.8 times over Ru cluster. The unique styrene oxide selectivity is attributed to the isolated single‐atom Ru anchoring on the Lewis acid site (AlOH) of Beta zeolite, which hinders the further ring opening of styrene oxide to phenylacetaldehyde and cleavage of the double bond of styrene to benzaldehyde.