Catalytically active interfaces in titania nanorod-supported copper catalysts for CO oxidation
Autor: | Wajid Ali Khan, Wey Yang Teoh, Xijun Hu, Season S. Chen, Alex C.K. Yip, Daniel C.W. Tsang, Frank Leung Yuk Lam |
---|---|
Rok vydání: | 2020 |
Předmět: |
Materials science
chemistry.chemical_element 02 engineering and technology Activation energy 010402 general chemistry 021001 nanoscience & nanotechnology Condensed Matter Physics 01 natural sciences Copper Atomic and Molecular Physics and Optics 0104 chemical sciences Catalysis chemistry.chemical_compound Adsorption Chemical engineering chemistry Chemisorption Titanium dioxide General Materials Science Nanorod Electrical and Electronic Engineering Temperature-programmed reduction 0210 nano-technology |
Zdroj: | Nano Research. 13:533-542 |
ISSN: | 1998-0000 1998-0124 |
Popis: | One-dimensional titanium dioxide nanorod (TNR)-supported Cu catalysts (2.5 wt.%–12.5 wt.%) were synthesized using deposition-precipitation. X-ray photoelectron spectroscopy, temperature programmed reduction and CO chemisorption measurements showed that Cu doping over TNR offered metal-support interactions and interfacial active sites that had a profound impact on the catalytic performance. The role of the Cu-TNR interface was investigated by comparing the catalytic activity of Cu-TNR catalysts with that of pure CuO nanoparticles in CO oxidation. The presence of highly dispersed copper species, a high number of interfacial active sites, CO adsorption capacity and surface/lattice oxygen were found to be responsible for the excellent activity of 7.5Cu-TNR (i.e., Cu loading of 7.5 wt.% on TNR). Moreover, the Cu-TNR catalysts followed the Langmuir-Hinshelwood reaction mechanism with 7.5Cu-TNR, exhibiting an apparent activation energy of 44.7 kJ/mol. The TNR-supported Cu catalyst gave the highest interfacial catalytic activity in medium-temperature CO oxidation (120-240 °C) compared to other commonly used supports, including titanium dioxide nanoparticles (TiO2-P25), silica (SiO2) and alumina (Al2O3) in which copper species were nonhomogeneously dispersed. This study confirms that medium-temperature CO oxidation is highly sensitive to the morphology and structure of the supporting material. |
Databáze: | OpenAIRE |
Externí odkaz: |