A DRIFTS study of CO adsorption and hydrogenation on Cu-based core–shell nanoparticles
- 5 January 2012
- journal article
- research article
- Published by Royal Society of Chemistry (RSC) in Catalysis Science & Technology
- Vol. 2 (3), 621-631
- https://doi.org/10.1039/c2cy00413e
Abstract
Core–shell nanoparticles are being considered for various applications due to their controllable atomic structure and improved properties compared to their bulk counterparts. In the present work, we have synthesized Cu@Mn3O4 and Cu@Co3O4 (core@shell) nanocatalysts using wet-chemical synthesis methods involving organic surfactants, and probed their surfaces using CO and H2 under reaction conditions using diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). The surfactant ligands used in the synthesis of the nanoparticles must be removed to allow access to the active catalyst sites. These ligands can be removed by oxidation, allowing adsorption of CO and H2. This work reports the DRIFTS results of CO adsorption and hydrogenation on Cu@Mn3O4 and Cu@Co3O4 nanoparticles after removing the ligands. The CO hydrogenation results were in agreement with the DRIFTS results, which suggested that the Cu@Co3O4 nanoparticles adsorb CO both dissociatively and associatively, creating a balance between molecular CO required for CO insertion and dissociated surface carbon species required for chain growth. This resulted in higher selectivities towards C2+ alcohols on this catalyst. On the other hand, the Cu@Mn3O4 nanoparticles showed a higher CO uptake and a lower CO dissociation activity, which resulted in a lower CHx concentration on the surface, thus limiting the rate of the CO insertion step required to form higher alcohols.Keywords
This publication has 59 references indexed in Scilit:
- Development of cobalt–copper nanoparticles as catalysts for higher alcohol synthesis from syngasCatalysis Today, 2009
- A Review of Recent Literature to Search for an Efficient Catalytic Process for the Conversion of Syngas to EthanolEnergy & Fuels, 2008
- Heterogeneous catalytic synthesis of ethanol from biomass-derived syngasChemical Society Reviews, 2007
- Characterization of copper-cobalt catalysts for alcohol synthesis from syngasApplied Catalysis A: General, 1994
- Evolution of Alcohol Synthesis Catalysts under SyngasIndustrial & Engineering Chemistry Research, 1994
- Promoter action of rare earth oxides in rhodium/silica catalysts for the conversion of syngas to ethanolApplied Catalysis, 1987
- The effect of alkali promotion on CO hydrogenation over Rh/TiO2Journal of Catalysis, 1985
- Promoter action in Fischer-Tropsch catalysisJournal of Catalysis, 1985
- Infrared studies of metal additive effects on carbon monoxide chemisorption modes on silicon dioxide-supported rhodium-manganese, -titanium and iron catalystsThe Journal of Physical Chemistry, 1985
- The role of the support in CO hydrogenation selectivity of supported rhodiumFaraday Discussions of the Chemical Society, 1981