Low‐Temperature CO Oxidation over the Pt−TiN Interfacial Dual Sites. Issue 21 (31st August 2021)

• Record Type: Journal Article
• Authors: Yang, Yifei; Zhou, Linsen; Chen, Jun; Qiu, Ruizhi; Yao, Yunxi
• Is Part Of: ChemCatChem. Volume 13:Issue 21(2021)
• Page Start: 4610
• Page End: 4617
• Publication Date: 2021-08-31
• Subjects: Metal-nitride interface -- Pt nanoparticles -- Dual sites -- CO oxidation; Catalysis -- Periodicals; 541.39505
• DOI: 10.1002/cctc.202101060
• Languages: English
• ISSNs: 1867-3880

Abstract

Abstract: The metal‐support interfacial synergistic catalysis allows the competitive reaction steps to occur in close proximity at different sites, thus decreasing the activation barrier and improving the catalytic efficiency. Combining the structural characterization, reactivity assessments and density functional theory (DFT) calculations, it is found that highly dispersed Pt clusters on TiN substrates favor the formation of Pt−TiN interfacial dual sites, which are highly reactive for the low‐temperature CO oxidation with an apparent activation energy as low as 38.7 kJ mol −1, much less than that on the traditional Pt/TiO2 or Pt/SiO2 catalysts. At low temperature, the surface sites of Pt are saturated with CO adsorption due to its high adsorption energy and the molecular O2 dissociatively adsorbs on the Ti sites to form the titanium oxynitride (TiNx Oy ) skin with a low barrier of 0.1 eV. The O atoms binding on Ti sites readily react with the adjacent CO molecules adsorbed on the perimeter of Pt clusters to attain a catalytic cycle with a reaction barrier of 0.5 eV. The interfacial synergistic effect between Pt and TiN is the origin of the low temperature CO oxidation activity on the metal‐nitride catalysts. Abstract : Highly dispersed Pt clusters supported on TiN substrates favor the formation of highly reactive dual sites. Molecular O2 dissociatively adsorbs on the Ti−Ti bridge sites to form titanium oxynitride (TiNx Oy ) skin and the oxygen atom binding on Ti sites readily react with the adjacent CO adsorbed on Pt to attain the catalytic cycle. The interfacial synergistic effect between Pt and TiN results in superior performance in the low‐temperature CO oxidation.