Facile benzene reduction promoted by a synergistically coupled Cu-Co-Ce ternary mixed oxide

• Published in: Chemical science (Cambridge) Vol. 11; no. 22; pp. 5766 - 5771
• Main Authors: Chen, Hao, Lin, Wenwen, Zhang, Zihao, Yang, Zhenzhen, Jie, Kecheng, Fu, Jie, Yang, Shi-ze, Dai, Sheng
• Format: Journal Article
• Language: English
• Published: England Royal Society of Chemistry 14.06.2020; Royal Society of Chemistry (RSC)
• Subjects: Aromatic compounds; Benzene; Catalysts; Cerium oxides; Chemistry; Cobalt oxides; Hydrocarbons; Hydrogen storage; Hydrogenation; INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Lattices; Metal oxides; Noble metals; Palladium; Pretreatment
• ISSN: 2041-6520; 2041-6539
• DOI: 10.1039/d0sc02238a

Hydrogenation of aromatic rings promoted by earth-abundant metal composites under mild conditions is an attractive and challenging subject in the long term. In this work, a simple active site creation and stabilization strategy was employed to obtain a Cu + -containing ternary mixed oxide catalyst. Simply by pre-treatment of the ternary metal oxide precursor under a H 2 atmosphere, a Cu + -derived heterogeneous catalyst was obtained and denoted as Cu 1 Co 5 Ce 5 O x . The catalyst showed (1) high Cu + species content, (2) a uniform distribution of Cu + doped into the lattices of CoO x and CeO 2 , (3) formation of CoO x /CuO x and CeO 2 /CuO x interfaces, and (4) a mesoporous structure. These unique properties of Cu 1 Co 5 Ce 5 O x endow it with pretty high hydrogenation activity for aromatic rings under mild conditions (100 °C with 5 bar H 2 ), which is much higher than that of the corresponding binary counterparts and even exceeds the performance of commercial noble metal catalysts ( e.g. Pd/C). The synergetic effect plays a crucial role in the catalytic procedure with CeO 2 functioning as a hydrogen dissociation and transfer medium, Cu + hydrogenating the benzene ring and CoO x stabilizing the unstable Cu + species. This will unlock a new opportunity to design highly efficient earth-abundant metal-derived heterogeneous catalysts via interface interactions. Hydrogenation of aromatic rings promoted by earth-abundant metal composites under mild conditions is an attractive and challenging subject in the long term.