Efficient oxygen storage property of Sr-Fe mixed oxide as automotive catalyst support
Efficient oxygen storage property of Sr-Fe mixed oxide as automotive catalyst support
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DOI：
10.1039/c8ta08378a
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发表时间：
2019-01-21
影响因子：
11.9
通讯作者：
Tanaka, Tsunehiro
中科院分区：
文献类型：
--
作者：
Beppu, Kosuke;Hosokawa, Saburo;Tanaka, Tsunehiro
用于从汽车废气中去除氮氧化物（NOx）的催化系统的效率受到废气中的氧浓度的强烈影响。为了克服这个问题，在净化系统中使用了储氧材料。本研究表明，NO还原在不同的氧浓度下的Pd/Sr 3Fe 2 O 7-δ催化剂，其中Fe部分取代由其他过渡金属（Mn，Co，Ni和Cu）。具有层状钙钛矿结构的Pd/Sr-3（Fe0.8Ni0.2）（2）O 7-δ催化剂在较宽的氧浓度范围内表现出最高的NO还原活性。发现Ni 3+取代了Sr 3Fe 2 O 7 δ中的Fe 3+而不是Fe 4+。Pd/Sr-3（Fe 0.8Ni 0.2）（2）O-7 δ比Pd/Sr 3Fe 2 O 7-δ具有更高的储氧能力，这是由于在氧释放/储存过程中伴随着Fe 4 +/Fe 3+氧化还原反应的Ni 3+和Ni 2+之间的氧化还原反应。该研究为新型钙钛矿结构催化剂的设计提供了有用的信息。
The efficiency of catalytic systems for the removal of nitrogen oxides (NOx) from automotive exhaust gases is strongly affected by the oxygen concentration in the exhaust gas. To overcome this problem, an oxygen storage material has been used in the purification systems. This study demonstrates the NO reduction under various oxygen concentrations over Pd/Sr3Fe2O7-delta catalysts in which Fe is partially replaced by other transition metals (Mn, Co, Ni, and Cu). Pd/Sr-3(Fe0.8Ni0.2)(2)O7-delta with a layered perovskite structure showed the highest NO reduction activity among the examined catalysts under a wide range of oxygen concentrations. Ni3+ was found to replace Fe3+ rather than Fe4+ in Sr3Fe2O7 delta. Pd/Sr-3(Fe0.8Ni0.2)(2)O-7 delta showed significantly improved oxygen storage capacity as compared to Pd/Sr3Fe2O7-delta, which was attributed to the redox between Ni3+ and Ni2+ accompanying the Fe4+/Fe3+ redox reaction during oxygen release/storage processes. This study provides useful information for the design of novel catalysts with a perovskite-type structure.