URI | http://purl.tuc.gr/dl/dias/69BBDDC6-30C1-4DBB-A84E-37E7E212E36C | - |
Identifier | https://doi.org/10.1016/j.jcou.2020.101408 | - |
Identifier | https://www.sciencedirect.com/science/article/pii/S2212982020310386 | - |
Language | en | - |
Extent | 12 pages | en |
Title | Effect of alkali (Cs) doping on the surface chemistry and CO2 hydrogenation performance of CuO/CeO2 catalysts | en |
Creator | Varvoutis Georgios | en |
Creator | Lykaki Maria | en |
Creator | Λυκακη Μαρια | el |
Creator | Papista Eleni | en |
Creator | Carabineiro, Sónia A. C | en |
Creator | Psarras Antonios C. | en |
Creator | Marnellos Georgios E. | en |
Creator | Konsolakis Michail | en |
Creator | Κονσολακης Μιχαηλ | el |
Publisher | Elsevier | en |
Content Summary | The reaction of captured carbon dioxide with renewable hydrogen towards the eventual indirect production of liquid hydrocarbons via CO2 reduction to CO (reverse water-gas shift reaction, rWGS) is a promising pathway in the general scheme of worldwide CO2 valorization. Copper-ceria oxides have been largely employed as rWGS catalysts owing to their unique properties linked to copper-ceria interactions. Here, we report on the fine-tuning of CuO/CeO2 composites by means of alkali promotion. In particular, this work aims at exploring the effect of cesium doping (0–4 atoms Cs per nm2) on co-precipitated CuO/CeO2 catalysts under CO2 hydrogenation conditions. The as-prepared samples were characterized by N2 physisorption, X-ray diffraction (XRD), H2-temperature programmed reduction (H2-TPR), X-ray photoelectron spectroscopy (XPS), CO2-temperature programmed desorption (CO2-TPD), Fourier-transform infrared spectroscopy (FTIR) of pyridine adsorption and CO-diffuse reflectance Fourier-transform infrared spectroscopy (CO-DRIFTS). The results demonstrated that a low amount of Cs exerted a beneficial effect on CO selectivity, inhibiting, however, CO2 conversion. Specifically, a doping of 2 atoms Cs per nm2 offers > 96 % CO selectivity and equilibrium CO2 conversion at temperatures as low as 430 °C, whereas further increase in cesium loading had no additional impact. The present findings can be mainly interpreted on a basis of the alkali effect on the textural and acid/base properties; Cs doping results in a significant reduction of the surface area and thus to a lower population of active sites for CO2 conversion, whereas it enhances the formation of basic sites and the stabilization of partially reduced Cu+ species, favoring CO selectivity. | en |
Type of Item | Peer-Reviewed Journal Publication | en |
Type of Item | Δημοσίευση σε Περιοδικό με Κριτές | el |
License | http://creativecommons.org/licenses/by/4.0/ | en |
Date of Item | 2022-08-01 | - |
Date of Publication | 2021 | - |
Subject | CO hydrogenation | en |
Subject | Reverse water-gas shift reaction | en |
Subject | CO Selectivity | en |
Subject | Copper-ceria | en |
Subject | Alkali doping | en |
Subject | Cs promotion | en |
Bibliographic Citation | G. Varvoutis, M. Lykaki, E. Papista, S. A. C. Carabineiro, A. C. Psarras, G. E. Marnellos, and M. Konsolakis, “Effect of alkali (Cs) doping on the surface chemistry and CO2 hydrogenation performance of CuO/CeO2 catalysts,” J. CO2 Util., vol. 44, Feb. 2021, doi: 10.1016/j.jcou.2020.101408. | en |