Cu-OFF/ERI Zeolite: Intergrowth Structure Synergistically Boosting Selective Catalytic Reduction of NO x with NH 3

作者：Jinfeng Han, Junyan Li, Wenru Zhao, Lin Li, Mengyang Chen, Xin Ge, Sen Wang, Qingling Liu, Donghai Mei, Jihong Yu · 发表于：Journal of the American Chemical Society · 年份：2024 · DOI：10.1021/jacs.3c13855 · 被引用次数：48 · 研究领域：Catalytic Processes in Materials Science、Nanomaterials for catalytic reactions、Ammonia Synthesis and Nitrogen Reduction

Cu-SSZ-13 has been commercialized for selective catalytic reduction with ammonia (NH 3 –SCR) to remove NO x from diesel exhaust. As its synthesis usually requires toxic and costly organic templates, the discovery of alternative Cu-based zeolite catalysts with organotemplate-free synthesis and comparable or even superior NH 3 –SCR activity to that of Cu-SSZ-13 is of great academic and industrial significance. Herein, we demonstrated that Cu-T with an intergrowth structure of offretite ( OFF ) and erionite ( ERI ) synthesized by an organotemplate-free method showed better catalytic performance than Cu-ERI and Cu-OFF as well as Cu-SSZ-13. Structure characterizations and density functional theory calculations indicated that the intergrowth structure promoted more isolated Cu 2+ located at the 6MR of the intergrowth interface, resulting in a better hydrothermal stability of Cu-T than Cu-ERI and Cu-OFF. Strikingly, the low-temperature activity of Cu-T significantly increased after hydrothermal aging, while that of Cu-ERI and Cu-OFF substantially decreased. Based on in situ diffuse reflectance infrared Fourier transform spectra analysis and density functional theory calculations, the reason can be attributed to the fact that NH 4 NO 3 formed on the Cu x O y species within ERI polymorph of Cu-T underwent a fast SCR reaction pathway with the assistance of Brønsted acid sites at the intergrowth interfaces under standard SCR reaction conditions. Significantly, Cu-T exhibited a wider tem...