Low-temperature carbon monoxide oxidation catalysed by regenerable atomically dispersed palladium on alumina
Low-temperature carbon monoxide oxidation catalysed by regenerable atomically dispersed palladium on alumina
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氧化铝上可再生原子分散钯催化的低温一氧化碳氧化
DOI：
10.1038/ncomms5885
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发表时间：
2014-09-01
影响因子：
16.6
通讯作者：
Datye, Abhaya K.
中科院分区：
文献类型：
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作者：
Peterson, Eric J.;Delariva, Andrew T.;Datye, Abhaya K.
贵金属的单个孤立原子催化最近引起了人们的极大兴趣，因为它有望实现原子效率的终极目标。以前的大多数报道都是关于可还原氧化物载体的。在这里，我们展示了孤立的钯原子可以在工业上相关的γ-氧化铝载体上催化活性。向氧化铝中添加氧化镧也有助于稳定孤立的钯原子。长期以来，氧化镧一直以提高氧化铝稳定性而闻名。经像差校正的扫描电子显微镜和操纵面X射线吸收光谱证实了γ-Al_2O_3表面存在掺杂的钯和镧。一氧化碳氧化反应活性测试表明，催化剂在40 °C时开始活性，在70 0 °C空气中氧化可再生催化剂活性。这些离子钯物种的高温稳定性和可再生性使该催化剂体系成为低温废气处理催化剂的潜在兴趣。
Catalysis by single isolated atoms of precious metals has attracted much recent interest, as it promises the ultimate in atom efficiency. Most previous reports are on reducible oxide supports. Here we show that isolated palladium atoms can be catalytically active on industrially relevant γ-alumina supports. The addition of lanthanum oxide to the alumina, long known for its ability to improve alumina stability, is found to also help in the stabilization of isolated palladium atoms. Aberration-corrected scanning transmission electron microscopy and operando X-ray absorption spectroscopy confirm the presence of intermingled palladium and lanthanum on the γ-alumina surface. Carbon monoxide oxidation reactivity measurements show onset of catalytic activity at 40 °C. The catalyst activity can be regenerated by oxidation at 700 °C in air. The high-temperature stability and regenerability of these ionic palladium species make this catalyst system of potential interest for low-temperature exhaust treatment catalysts.