Cu-modified cryptomelane oxide as active catalyst for CO oxidation reactions

2012 ◽  
Vol 123-124 ◽  
pp. 27-35 ◽  
Author(s):  
Willinton Y. Hernández ◽  
Miguel A. Centeno ◽  
Svetlana Ivanova ◽  
Pierre Eloy ◽  
Eric M. Gaigneaux ◽  
...  
2019 ◽  
Author(s):  
Wugen Huang ◽  
qingfei liu ◽  
Zhiwen Zhou ◽  
Yangsheng Li ◽  
Yong Wang ◽  
...  

Despite tremendous importance in catalysis, the design and improvement of the oxide- metal interface has been hampered by the limited understanding on the nature of interfacial sites, as well as the oxide-metal interaction (OMI). Through the construction of well-defined Cu<sub>2</sub>O-Pt, Cu<sub>2</sub>O-Ag, Cu<sub>2</sub>O-Au interfaces, we found that Cu<sub>2</sub>O Nanostructures (NSs) on Pt exhibit much lower thermal stability than on Ag and Au, although they show the same surface and edge structures, as identified by element-specific scanning tunneling microscopy (ES-STM) images. The activities of the Cu<sub>2</sub>O-Pt and Cu<sub>2</sub>O-Au interfaces for CO oxidation were further compared at the atomic scale and showed in general that the interface with Cu<sub>2</sub>O NSs could annihilate the CO-poisoning problem suffered by Pt group metals and enhance the interaction with O<sub>2</sub>, which is a limiting step for CO oxidation catalysis on group IB metals. While both interfaces could react with CO at room temperature, the OMI was found to determine the reactivity of supported Cu<sub>2</sub>O NSs by 1) tuning the activity of interfacial oxygen atoms and 2) stabilizing oxygen vacancies or vice versa, the dissociated oxygen atoms at the interface. Our study provides new insight for OMI and for the development of Cu-based catalysts for low temperature oxidation reactions.


2019 ◽  
Author(s):  
Wugen Huang ◽  
Yangsheng Li ◽  
Yong Wang ◽  
Yunchuan Tu ◽  
Dehui Deng ◽  
...  

Despite tremendous importance in catalysis, the design and improvement of the oxide- metal interface has been hampered by the limited understanding on the nature of interfacial sites, as well as the oxide-metal interaction (OMI). Through the construction of well-defined Cu<sub>2</sub>O-Pt, Cu<sub>2</sub>O-Ag, Cu<sub>2</sub>O-Au interfaces, we found that Cu<sub>2</sub>O Nanostructures (NSs) on Pt exhibit much lower thermal stability than on Ag and Au, although they show the same surface and edge structures, as identified by element-specific scanning tunneling microscopy (ES-STM) images. The activities of the Cu<sub>2</sub>O-Pt and Cu<sub>2</sub>O-Au interfaces for CO oxidation were further compared at the atomic scale and showed in general that the interface with Cu<sub>2</sub>O NSs could annihilate the CO-poisoning problem suffered by Pt group metals and enhance the interaction with O<sub>2</sub>, which is a limiting step for CO oxidation catalysis on group IB metals. While both interfaces could react with CO at room temperature, the OMI was found to determine the reactivity of supported Cu<sub>2</sub>O NSs by 1) tuning the activity of interfacial oxygen atoms and 2) stabilizing oxygen vacancies or vice versa, the dissociated oxygen atoms at the interface. Our study provides new insight for OMI and for the development of Cu-based catalysts for low temperature oxidation reactions.


2019 ◽  
Author(s):  
Yong Li ◽  
Shikun Li ◽  
Marcus Bäumer ◽  
Lyudmila V. Moskaleva

Oxidation reactions catalyzed by Au nanoparticles supported on reducible oxides have been widely studied both experimentally and theoretically, whereas <i>inverse catalysts</i>, in which oxide nanoparticles are supported on metal surfaces, received considerably less attention. In both systems catalytic activity at metal – oxide interfaces can arise not only from each material contributing its functionality, but also from their interactions creating properties beyond the sum of individual components. Inverse catalysts may retain the synergy between the metal and oxide functionalities, while offering further specific advantages, e.g. a possibility to have better control over interfacial sites or to yield improved stability, activity, and selectivity. Our work provides the mechanism of O atom/vacancy diffusion-assisted Mars-van-Krevelen CO oxidation on gold-supported ceria nanoparticle through state-of-the-art ab initio molecular dynamic simulation studies.


Author(s):  
Zheng Wang ◽  
Omeir Khalid ◽  
Wei Wang ◽  
Yu Wang ◽  
Tim Weber ◽  
...  

The effect of the carrier material on the intrinsic activity of three catalytic total oxidation reactions, namely CO oxidation as well as methane and propane combustion over highly dispersed RuO2...


2011 ◽  
Vol 106 (3-4) ◽  
pp. 621-629 ◽  
Author(s):  
O.H. Laguna ◽  
M.A. Centeno ◽  
M. Boutonnet ◽  
J.A. Odriozola

2007 ◽  
Vol 91 (2) ◽  
pp. 213-221 ◽  
Author(s):  
Maela Manzoli ◽  
Floriana Vindigni ◽  
Anna Chiorino ◽  
Tatyana Tabakova ◽  
Vasko Idakiev ◽  
...  

Catalysts ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 411 ◽  
Author(s):  
Kamel Eid ◽  
Yahia Ahmad ◽  
Assem Mohamed ◽  
Anas Elsafy ◽  
Siham Al-Qaradawi

Developing efficient catalyst for CO oxidation at low-temperature is crucial in various industrial and environmental remediation applications. Herein, we present a versatile approach for controlled synthesis of carbon nitride nanowires (CN NWs) doped with palladium and copper (Pd/Cu/CN NWs) for CO oxidation reactions. This is based on the polymerization of melamine by nitric acid in the presence of metal-precursors followed by annealing under nitrogen. This intriguingly drove the formation of well-defined, one-dimensional nanowires architecture with a high surface area (120 m2 g−1) and doped atomically with Pd and Cu. The newly-designed Pd/Cu/CN NWs fully converted CO to CO2 at 149 °C, that was substantially more active than that of Pd/CN NWs (283 °C) and Cu/CN NWs (329 °C). Moreover, Pd/Cu/CN NWs fully reserved their initial CO oxidation activity after 20 h. This is mainly attributed to the combination between the unique catalytic properties of Pd/Cu and outstanding physicochemical properties of CN NWs, which tune the adsorption energies of CO reactant and reaction product during the CO oxidation reaction. The as-developed method may open new frontiers on using CN NWs supported various noble metals for CO oxidation reaction.


2012 ◽  
Vol 287 ◽  
pp. 30-36 ◽  
Author(s):  
Krisztina Frey ◽  
Viacheslav Iablokov ◽  
György Sáfrán ◽  
János Osán ◽  
István Sajó ◽  
...  

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