CO adsorption, activation, and oxidation on CeO_(2)(111)-supported Fe model catalyst surfaces  

作　　者：Xingwang Cheng Yi Tu Dongling Zhang Dong Han Luchao Huang Jun Hu Honghe Ding Qian Xu Junfa Zhu 

机构地区：[1]National Synchrotron Radiation Laboratory,University of Science and Technology of China,Hefei 230029,China [2]Department of Chemical Physics,Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes,and Key Laboratory of Precision and Intelligent Chemistry,University of Science and Technology of China,Hefei 230026,China

出　　处：《Nano Research》2025年第2期111-119,共9页纳米研究(英文版)

基　　金：This work was financially supported by the National Key R&D Program of China(No.2023YFA1509103);the National Natural Science Foundation of China(Nos.22272157,21872131,22106085,and U1932214).

摘　　要：Elucidating the synergistic effect of Fe on CeO_(2) is challenging in CO-related reactions but attractive owing to the improvement in the oxygen storage/release capacity of ceria with the addition of Fe.Here,using CeO_(2)(111)-supported Fe model catalysts,CO adsorption,activation,and oxidation on catalyst surfaces was carefully investigated using synchrotron radiation photoemission spectroscopy(SRPES),temperature-programmed desorption(TPD),and infrared reflection absorption spectroscopy(IRRAS).The precursorπ-bonding state for CO dissociative adsorption has been identified through unusually low CO vibration frequencies and a low 0 ML 0.6 ML Top sites Bridge sites MS intensity 1.0 MLπ-bond state 2.0 ML Fe 3p hv=180 eV 100 L CO on 1.6 ML Fe/CeO_(2)(111)54.7 eV Fe^(2+)53.3 eV Fe 01142 cm−1 Recombination desorption Intensity(a.u.)Clean 100 L 150 K 200 K 250 K 300 K 400 K 600 K 100200300400500600700 Temperature(K)6058565452 Binding energy(eV)50 dissociation temperature on Fe/CeO_(2)(111)surfaces.CO is oxidized by dissociated atomic O followed by the Langmuir–Hinshelwood mechanism,whereas the lattice oxygen of CeO_(2) exhibits low activity.The CO_(2) yield displays a volcanic curve as a function of Fe coverage.On the 0.6 ML Fe/CeO_(2) surface,weakly bound atomic O on Fe^(2+)results in the best catalytic activity.While on high Fe coverage surfaces,the CO_(2) yield is limited due to the capture of atomic O by Fe0.Our results provide comprehensive insights into the adsorption,activation,and oxidation of CO on Fe/CeO_(2) and identify the reaction mechanism,and the active site,which provides deeper insights into CO-related reaction mechanisms over CeO_(2) supported Fe catalysts.

关 键 词：iron/ceria model catalyst adsorption ACTIVATION OXIDATION 

分 类 号：O64[理学—物理化学]