Generation and reactivity of putative support systems, Ce-Al neutral binary oxide nanoclusters: CO oxidation and C–H bond activation

摘要: Both ceria (CeO2) and alumina (Al 2O3) are very important catalyst support materials. Neutral binary oxide nanoclusters (NBONCs), Ce x Al y O z , generated detected in the gas phase their reactivity with carbon monoxide (CO) butane (C4H10) is studied. The active species CeAlO4 • can react CO via atom transfer (OAT) H (HAT), respectively. Other NBONCs do not show reactivities toward C4H10. structures, as well reactivities, of studied theoretically employing density functional theory (DFT) calculations. ground state NBONC possesses a kite-shaped structure an OtCeObObAlOt configuration (Ot, terminal oxygen; Ob, bridging oxygen). An unpaired electron localized on Ot AlOt moiety rather than CeOt moiety: this centered radical plays role for NBONC. Ce2O4, •, 2O4 compared, emphasizing importance spin-localized oxygen these reactions. Intramolecular charge distributions appear to play neutral clusters, but could be charged isoelectronic BONCs. DFT studies that reaction C4H10 form CeAlO4H•C4H9 encounter complex barrierless. While HAT processes have been previously characterized cationic anionic reported study first observation process supported by cluster. Mechanisms catalytic oxidation over surfaces /M m n or M /Al materials proposed consistent presented experimental theoretical results.