Structure-Activity Relationship of Iron Oxides for NO reduction in the presence of C3H6, CO, and O2
Structure-Activity Relationship of Iron Oxides for NO reduction in the presence of C3H6, CO, and O2
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C3H6、CO 和 O2 存在下氧化铁还原 NO 的构效关系
DOI：
10.1002/chem.201902994
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发表时间：
2019
期刊：
影响因子：
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通讯作者：
A. Satsuma
中科院分区：
文献类型：
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作者：
K. Ueda;J. Ohyama;K. Sawabe;A. Satsuma
尖晶石型NiFe 2 O 4在模拟汽油动力车辆的排气下表现出贱金属氧化物中最高的NO还原活性。铁氧化物的结构-活性关系已通过实验和计算研究。尖晶石型氧化铁（γ-Fe 2 O3）的NO还原活性远高于其他结构的氧化铁（α-Fe 2 O3和LaFeO 3）。Operando IR测量澄清，尖晶石结构促进NOx和吸附的氧化烃或氰化物物种之间的反应。尖晶石结构的高反应性归因于NO的高吸附能，如通过DFT计算所阐明的。此外，分子轨道计算表明，尖晶石型氧化铁的局域配位结构导致NO在Fe原子上的吸附不仅涉及σ轨道，而且涉及π轨道.这项工作阐明了金属氧化物结构依赖性活性的起源，重点关注其局部配位结构。
Spinel‐type NiFe2O4exhibited the highest NO reduction activity among base‐metal oxides under simulated exhaust of a gasoline‐powered vehicle. The structure–activity relationship of iron oxides has been investigated through both experimental and computational studies. Spinel iron oxide (γ‐Fe2O3) exhibited a much higher NO reduction activity than that of iron oxide with other structures (α‐Fe2O3and LaFeO3). Operando IR measurements clarified that the spinel structure facilitated the reaction between NOxand adsorbed oxidized hydrocarbon or cyanide species. The high reactivity of the spinel structure was ascribed to the high adsorption energy of NO, as elucidated by DFT calculations. Furthermore, molecular orbital calculations demonstrated that the local coordination structure of the spinel iron oxide induced the involvement of not onlyσbut alsoπorbitals during NO adsorption on Fe atoms. This work clarified the origin of the structure‐dependent activity of metal oxides, with a focus on their local coordination structures.