H+−H− Pairs in Partially Oxidized MAX Phases for Bifunctional Catalytic Conversion of Furfurals into Linear Ketones. (17th October 2022)

• Record Type: Journal Article
• Authors: Deng, Qiang; Zhou, Rong; Zhang, Yong‐Chao; Li, Xiang; Li, Jiahui; Tu, Shaobo; Sheng, Guan; Wang, Jun; Zeng, Zheling; Yoskamtorn, Tatchamapan; Edman Tsang, Shik Chi
• Is Part Of: Angewandte Chemie. Volume 135:Number 9(2023)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-10-17
• Subjects: Acidity -- Frustrated Lewis Pairs -- Hydrogenation -- MAX Phases -- Synergistic Reactions; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.202211461
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: Currently, less favorable C=O hydrogenation and weak concerted acid catalysis cause unsatisfactory catalytic performance in the upgrading of biomass‐derived furfurals (i.e., furfural, 5‐methyl furfural, and 5‐hydroxymethyl furfural) to ketones (i.e., cyclopentanone, 2, 5‐hexanedione, and 1‐hydroxyl‐2, 5‐hexanedione). A series of partially oxidized MAX phase (i.e., Ti3 AlC2, Ti2 AlC, Ti3 SiC2 ) supporting Pd catalysts were fabricated, which showed high catalytic activity; Pd/Ti3 AlC2 in particular displayed high performance for conversion of furfurals into targeted ketones. Detailed studies of the catalytic mechanism confirm that in situ hydrogen spillover generates Frustrated Lewis H + −H − pairs, which not only act as the hydrogenation sites for selective C=O hydrogenation but also provide acid sites for ring opening. The close intimate hydrogenation and acid sites promote bifunctional catalytic reactions, substantially reducing the reported minimum reaction temperature of various furfurals by at least 30–60 °C. Abstract : Frustrated Lewis H + −H − pairs, generated in situ by hydrogen spillover on partially oxidized MAX phases, act as the hydrogenation sites for C=O hydrogenation and provide acid sites for ring opening. The close intimate hydrogenation and acid sites demonstrate unprecedented bifunctional catalytic performance for the conversion of furfurals.