Catalysis and In Situ Studies of Rh1/Co3O4 Nanorods in Reduction of NO with H2

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• 作者：Lei Wang ; Shiran Zhang ; Yuan Zhu ; Anitha Patlolla ; Junjun Shan ; Hideto Yoshida ; Seiji Takeda ; Anatoly I. Frenkel ; Franklin (Feng) Tao
• 刊名：ACS Catalysis
• 出版年：2013
• 出版时间：May 3, 2013
• 年：2013
• 卷：3
• 期：5
• 页码：1011-1019
• 全文大小：625K
• 年卷期：v.3,no.5(May 3, 2013)
• ISSN：2155-5435

文摘

Efficient use of precious metal atoms in heterogeneous catalysis is important in chemical transformation and environmental remediation. Co₃O₄ with singly dispersed Rh atoms, Rh₁/Co₃O₄, was synthesized for reduction of nitric oxide with hydrogen. Studies using extended X-ray absorption fine structure (EXAFS) showed that the singly dispersed Rh atoms are bonded to surface oxygen atoms before catalysis. In situ studies using ambient pressure X-ray photoelectron spectroscopy (AP-XPS), EXAFS, and X-ray Absorption Near Edge Structure (XANES) suggested that the surface of Rh₁/Co₃O₄ with singly dispersed Rh atoms is restructured into a new geometry at 220 掳C in the mixture of reactant gases (NO and H₂). It forms RhCo_n nanoclusters singly dispersed in the surface layer of Co₃O₄. The restructured catalyst, RhCo_n/Co₃O₄ exhibits a much better catalytic performance in contrast to Rh₁/Co₃O₄ without a restructuring. RhCo_n/Co₃O₄ is highly active for reduction of nitric oxide with hydrogen. Selectivity to the production of N₂ at 220 掳C is 87% and reaches 97% at 300 掳C. In situ studies showed this catalyst maintains its single dispersion of Rh atoms up to 300 掳C during catalysis.

Keywords:

nanocatalysis; in situ study; Co₃O₄; ambient pressure XPS; nitric oxide