Journal ArticleDOI
Following the structure of copper-zinc-alumina across the pressure gap in carbon dioxide hydrogenation
Arik Beck,Maxim Zabilskiy,Mark A. Newton,Olga V. Safonova,Marc Willinger,Jeroen A. van Bokhoven,Jeroen A. van Bokhoven +6 more
- Vol. 4, Iss: 6, pp 488-497
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TLDR
In this paper, the state and evolution of the catalyst is defined by its environment, and the structure of the catalysts shows a strong pressure dependence, especially below 1 bar, which is a general problem in catalysis.Abstract:
Copper-zinc-alumina catalysts are used industrially for methanol synthesis from feedstock containing carbon monoxide and carbon dioxide. The high performance of the catalyst stems from synergies that develop between its components. This important catalytic system has been investigated with a myriad of approaches, however, no comprehensive agreement on the fundamental source of its high activity has been reached. One potential source of disagreement is the considerable variation in pressure used in studies to understand a process that is performed industrially at pressures above 20 bar. Here, by systematically studying the catalyst state during temperature-programmed reduction and under carbon dioxide hydrogenation with in situ and operando X-ray absorption spectroscopy over four orders of magnitude in pressure, we show how the state and evolution of the catalyst is defined by its environment. The structure of the catalyst shows a strong pressure dependence, especially below 1 bar. As pressure gaps are a general problem in catalysis, these observations have wide-ranging ramifications. Copper-zinc-alumina is used in industry to catalyse the synthesis of methanol from CO2, but many aspects of its high performance remain elusive. Now, by using in situ and operando techniques over four orders of magnitude in pressure, the authors show how the catalyst structure and kinetics change with the applied conditions.read more
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Journal ArticleDOI
Dynamic interplay between metal nanoparticles and oxide support under redox conditions
TL;DR: Frey et al. as discussed by the authors showed that the strong metal-support interaction (SMSI)-induced encapsulation of platinum particles on titania observed under reducing conditions is lost once the system is exposed to a redox-reactive environment containing oxygen and hydrogen at a total pressure of ~1 bar.
Journal ArticleDOI
The role of Cu1–O3 species in single-atom Cu/ZrO2 catalyst for CO2 hydrogenation
Huibo Zhao,Ruofan Yu,Sicong Ma,Kaizhuang Xu,Yang Chen,Kun Jiang,Yuan Fang,Caixia Zhu,Xiao-Can Liu,Yu Tang,Lizhi Wu,Yingquan Wu,Qike Jiang,Peng He,Zhi-Pan Liu,Li Tan +15 more
TL;DR: In this paper , a single-atom Cu-Zr catalyst with isolated active copper sites for the hydrogenation of CO2 to methanol was reported, and it was shown that the presence of small copper clusters or nanoparticles with Cu-Cu structural patterns are responsible for forming the CO byproduct.
Journal ArticleDOI
Light‐Assisted CO <sub>2</sub> Hydrogenation over Pd <sub>3</sub> Cu@UiO‐66 Promoted by Active Sites in Close Proximity
TL;DR: In this article , tiny Pd3 Cu nanoparticles are confined into a metal-organic framework (MOF), UiO-66, to afford a methanol production rate of 340 μmol g-1 h-1 at 200 °C and 1.25 MPa under light irradiation, far surpassing that in the dark.
Journal ArticleDOI
The state of zinc in methanol synthesis over a Zn/ZnO/Cu(211) model catalyst
P. Amann,Bernhard Klötzer,David Degerman,Norbert Köpfle,Thomas Götschi,Patrick Lömker,Christoph Rameshan,Kevin Ploner,Djuro Bikaljevic,Hsin-Yi Wang,Markus Soldemo,Mikhail Shipilin,Christopher M. Goodwin,Jörgen Gladh,Joakim Halldin Stenlid,M. Börner,Christoph Schlueter,and Svante Nilsson +17 more
TL;DR: In this paper , the authors used x-ray photoelectron spectroscopy at 180 to 500 millibar to probe the nature of Zn and reaction intermediates during CO2/CO hydrogenation over Zn/ZnO/Cu(211), where the temperature is sufficiently high for the reaction to rapidly turn over, thus creating an almost adsorbate-free surface.
Journal ArticleDOI
Tailoring the Oxidation State of Metallic TiO through Ti3+/Ti2+ regulation for Photocatalytic Conversion of CO2 to C2H6
TL;DR: Based on the principle of charge balance, a co-doping strategy to adjust the surface oxidation state distribution of metallic catalysts was proposed in this paper , which showed that Zn and N adjust the valence states of adjacent Ti elements, so that the surface of TiO maintains a relatively stable Ti3+/Ti2+ ratio.
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