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Metal promotion could unlock high performance in zinc-zirconium catalysts, ZnZrOx, for CO2 hydrogenation to methanol. Still, with most efforts devoted to costly palladium, the optimal metal choice and necessary atomic-level architecture remain unclear. Herein, we investigate the promotion of ZnZrOx catalysts with small amounts (0.5 mol%) of diverse hydrogenation metals (Re, Co, Au, Ni, Rh, Ag, Ir, Ru, Pt, Pd, and Cu) prepared via a standardized flame spray pyrolysis approach. Cu emerges as the most effective promoter, doubling methanol productivity. Operando X-ray absorption, infrared, and electron paramagnetic resonance spectroscopic analyses and density functional theory simulations reveal that Cu0 species form Zn-rich low-nuclearity CuZn clusters on the ZrO2 surface during reaction, which correlates with the generation of oxygen vacancies in their vicinity. Mechanistic studies demonstrate that this catalytic ensemble promotes the rapid hydrogenation of intermediate formate into methanol while effectively suppressing CO production, showcasing the potential of low-nuclearity metal ensembles in CO2-based methanol synthesis.The ideal metal selection and atomic-level arrangement for catalysts in CO2 hydrogenation are still uncertain. Here, copper is identified as the most effective promoter for enhancing ZnZrOx catalysts when precisely structured into CuZn ensembles, offering new insights for designing superior catalysts for CO2-based methanol synthesis. [ABSTRACT FROM AUTHOR]

The implementation of supported metal catalysts heavily relies on the synergistic interactions between metal nanoparticles and the material they are dispersed on. It is clear that interfacial perimeter sites have outstanding skills for turning catalytic reactions over, however, high activity and selectivity of the designed interface‐induced metal distortion can also obtain catalysts for the most crucial industrial processes as evidenced in this paper. Herein, the beneficial synergy established between designed Pt nanoparticles and MnO in the course of the reverse water gas shift (RWGS) reaction resulted in a Pt/MnO catalyst having ≈10 times higher activity compared to the reference Pt/SBA‐15 catalyst with >99 % CO selectivity. Under activation, a crystal assembly through the metallic Pt (110) and MnO evolved, where the plane distance differences caused a mismatched‐row structure in softer Pt nanoparticles, which was identified by microscopic and surface‐sensitive spectroscopic characterizations combined with density functional theory simulations. The generated edge dislocations caused the Pt lattice expansion which led to the weakening of the Pt−CO bond. Even though MnO also exhibited an adverse effect on Pt by lowering the number of exposed metal sites, rapid desorption of the linearly adsorbed CO species governed the performance of the Pt/MnO in the RWGS. [ABSTRACT FROM AUTHOR]

Ternäre Pd‐In2O3/ZrO2 Katalysatoren beweisen technologisches Potenzial für die CO2‐basierte Methanolsynthese, wobei die Entwicklung skalierbarer Systeme und das Verständnis komplexer dynamischer Wechselwirkungen zwischen der aktiven Phase, des Promotors und des Trägers der Schlüssel zur Erreichung einer hohen Produktivität sind. Hier zeigen wir, dass durch einfache Imprägnierung hergestellte Pd‐In2O3/ZrO2 Katalysatoren unter CO2‐Hydrierbedingungen eine stabile und selektive Nanoarchitektur bilden, unabhängig von der Reihenfolge der Zugabe von Pd‐ und In‐Komponenten auf den Zirkonoxidträger. Detaillierte operando Charakterisierung und Simulationen deuten auf eine schnelle Umstrukturierung, dessen Treiber die Energie der Metall‐Metalloxid‐Wechselwirkung ist. Die Nähe von InOx‐Schichten auf den entstehenden InPdx‐Partikeln verhindern Leistungsverluste durch Pd‐Sinterung. Weiterhin unterstreichen die Ergebnisse die entscheidende Rolle der reaktionsinduzierten Umstrukturierung in komplexem CO2‐Hydrierkatalysatoren und bieten Einblicke in die optimale Integration von Säure‐Base‐ und Redoxfunktionen für die technische Umsetzung. [ABSTRACT FROM AUTHOR]

Ternary Pd‐In2O3/ZrO2 catalysts exhibit technological potential for CO2‐based methanol synthesis, but developing scalable systems and comprehending complex dynamic behaviors of the active phase, promoter, and carrier are key for achieving high productivity. Here, we show that the structure of Pd‐In2O3/ZrO2 systems prepared by wet impregnation evolves under CO2 hydrogenation conditions into a selective and stable architecture, independent of the order of addition of Pd and In phases on the zirconia carrier. Detailed operando characterization and simulations reveal a rapid restructuring driven by the metal‐metal oxide interaction energetics. The proximity of InPdx alloy particles decorated by InOx layers in the resulting architecture prevents performance losses associated with Pd sintering. The findings highlight the crucial role of reaction‐induced restructuring in complex CO2 hydrogenation catalysts and offer insights into the optimal integration of acid‐base and redox functions for practical implementation. [ABSTRACT FROM AUTHOR]

Mixed zinc‐zirconium oxides, ZnZrOx, are highly selective and stable catalysts for CO2 hydrogenation to methanol, a pivotal energy vector. However, their activity remains moderate, and descriptors to design improved systems are lacking. This work applies flame spray pyrolysis (FSP), a one‐step and scalable method, to synthesize a series of ZnZrOx catalysts, and systematically compares them to coprecipitated (CP) analogs to establish deeper synthesis–structure–performance relationships. FSP systems (up to 5 mol%) generally display a threefold higher methanol productivity compared to their CP counterparts. In‐depth characterization and theoretical simulations show that, unlike CP, FSP maximizes the surface area and formation of atomically dispersed Zn2+ sites incorporated in lattice positions within the ZrO2 surface, which is key to improving performance. Analysis by in situ electron paramagnetic resonance (EPR) spectroscopy reveals that the specific architecture of the flame‐made catalyst markedly fosters the generation of oxygen vacancies. Together with surrounding Zn and Zr‐O atoms, the oxygen vacancies create active ensembles that favor methanol formation through the formate path while suppressing undesired CO production, as confirmed by kinetic modeling. This study elucidates the nature of active sites and their working mechanism, pushing forward ZnZrOx‐catalyzed methanol synthesis by providing a new benchmark for this cost‐effective and earth‐abundant catalyst family. [ABSTRACT FROM AUTHOR]

Mixed zinc‐zirconium oxides, ZnZrOx, are highly selective and stable catalysts for CO2 hydrogenation to methanol, a pivotal energy vector. However, their activity remains moderate, and descriptors to design improved systems are lacking. This work applies flame spray pyrolysis (FSP), a one‐step and scalable method, to synthesize a series of ZnZrOx catalysts, and systematically compares them to coprecipitated (CP) analogs to establish deeper synthesis–structure–performance relationships. FSP systems (up to 5 mol%) generally display a threefold higher methanol productivity compared to their CP counterparts. In‐depth characterization and theoretical simulations show that, unlike CP, FSP maximizes the surface area and formation of atomically dispersed Zn2+ sites incorporated in lattice positions within the ZrO2 surface, which is key to improving performance. Analysis by in situ electron paramagnetic resonance (EPR) spectroscopy reveals that the specific architecture of the flame‐made catalyst markedly fosters the generation of oxygen vacancies. Together with surrounding Zn and Zr‐O atoms, the oxygen vacancies create active ensembles that favor methanol formation through the formate path while suppressing undesired CO production, as confirmed by kinetic modeling. This study elucidates the nature of active sites and their working mechanism, pushing forward ZnZrOx‐catalyzed methanol synthesis by providing a new benchmark for this cost‐effective and earth‐abundant catalyst family. [ABSTRACT FROM AUTHOR]

A plethora of metal promoters have been applied to enhance the performance of In2O3 in CO2 hydrogenation to methanol, a prospective energy carrier. However, the lack of systematic catalyst preparation and evaluation precludes a direct comparison of their speciation and promotional effects, and consequently, the design of an optimal system. Herein, flame spray pyrolysis (FSP) is employed as a standardized synthesis method to introduce nine metal promoters (0.5 wt.%) into In2O3. Methanol productivity generally increased on M‐In2O3 with selectivity following Pd ≈ Pt > Rh ≈ Ru ≈ Ir > Ni ≈ Co > Ag ≈ In2O3 > Au. In‐depth characterization, kinetic analyses, and theoretical calculations reveal a range of metal‐dependent speciation which dictate catalyst architecture and degree of promotion. Atomically‐dispersed promoters (Pd, Pt, Rh, Ru, and Ir) grant the highest improvement in performance, particularly Pd and Pt, which markedly promote hydrogen activation while hindering undesired CO formation. In contrast, metals in clustered (Ni and Co) and nanoparticle (Ag and Au) forms display moderate and no promotion, respectively. This study provides an atomic‐level understanding of In2O3 promotion based on a unified protocol, and highlights the potential of FSP to engineer complex catalytic systems toward more efficient energy transformations. [ABSTRACT FROM AUTHOR]

Keywords: CO2-Hydrierung; Metall-Metalloxid-Wechselwirkungen; Methanolsynthese; Operando Analyse; Pd-In2O3/ZrO2 Katalysator DE CO2-Hydrierung Metall-Metalloxid-Wechselwirkungen Methanolsynthese Operando Analyse Pd-In2O3/ZrO2 Katalysator 1 1 1 10/12/23 20231016 NES 231016 B Developing scalable systems b and understanding dynamic behaviors are crucial for advancing the technological potential of multicomponent catalysts for CO SB 2 sb -based methanol synthesis. In their Research Article (e202306563), Javier Pérez-Ramírez and co-workers show that the reaction-induced restructuring of Pd-In SB 2 sb O SB 3 sb /ZrO SB 2 sb systems, prepared via impregnation, leads to a unique architecture that integrates the necessary acid-base functionality of In SB 2 sb O SB 3 sb with the H SB 2 sb splitting ability of an InPd SB 2 sb alloy, while also ensuring high stability. [Extracted from the article]

Developing scalable systems and understanding dynamic behaviors are crucial for advancing the technological potential of multicomponent catalysts for CO2‐based methanol synthesis. In their Research Article (e202306563), Javier Pérez‐Ramírez and co‐workers show that the reaction‐induced restructuring of Pd‐In2O3/ZrO2 systems, prepared via impregnation, leads to a unique architecture that integrates the necessary acid‐base functionality of In2O3 with the H2 splitting ability of an InPd2 alloy, while also ensuring high stability. [ABSTRACT FROM AUTHOR]

Keywords: CO2 hydrogenation; flame spray pyrolysis; oxygen vacancies; sustainable methanol; ZnZrOx catalysts EN CO2 hydrogenation flame spray pyrolysis oxygen vacancies sustainable methanol ZnZrOx catalysts 1 1 1 04/17/23 20230413 NES 230413 B Methanol Synthesis b In article number 2204122, Javier Pérez-Ramírez and co-workers apply flame spray pyrolysis to design superior ZnZrO SB I x i sb catalysts for methanol synthesis from CO SB 2 sb . Design of Flame-Made ZnZrOx Catalysts for Sustainable Methanol Synthesis from CO2 (Adv. CO2 hydrogenation, flame spray pyrolysis, oxygen vacancies, sustainable methanol, ZnZrOx catalysts. [Extracted from the article]

CO 2 hydrogenation, green methanol, indium oxide, metal speciation, promotion Flame Spray Pyrolysis as a Synthesis Platform to Assess Metal Promotion in In2O3-Catalyzed CO2 Hydrogenation (Adv. Keywords: CO 2 hydrogenation; green methanol; indium oxide; metal speciation; promotion EN CO 2 hydrogenation green methanol indium oxide metal speciation promotion 1 1 1 04/18/22 20220414 NES 220414 B Flame Spray Pyrolysis b In article number 2103707, Núria López, Javier Pérez-Ramírez and co-workers apply flame spray pyrolysis as a standardized synthesis method to investigate promotional effects of nine transition metals in In SB 2 sb O SB 3 sb -catalyzed CO SB 2 sb hydrogenation to methanol, revealing that catalyst architecture (single atoms, clusters, and nanoparticles) and corresponding reactivity are dictated by the nature of the promoter. [Extracted from the article]

The implementation of supported metal catalysts heavily relies on the synergistic interactions between metal nanoparticles and the material they are dispersed on. It is clear that interfacial perimeter sites have outstanding skills for turning catalytic reactions over, however, high activity and selectivity of the designed interface-induced metal distortion can also obtain catalysts for the most crucial industrial processes as evidenced in this paper. Herein, the beneficial synergy established between designed Pt nanoparticles and MnO in the course of the reverse water gas shift (RWGS) reaction resulted in a Pt/MnO catalyst having ≈10 times higher activity compared to the reference Pt/SBA-15 catalyst with >99 % CO selectivity. Under activation, a crystal assembly through the metallic Pt (110) and MnO evolved, where the plane distance differences caused a mismatched-row structure in softer Pt nanoparticles, which was identified by microscopic and surface-sensitive spectroscopic characterizations combined with density functional theory simulations. The generated edge dislocations caused the Pt lattice expansion which led to the weakening of the Pt-CO bond. Even though MnO also exhibited an adverse effect on Pt by lowering the number of exposed metal sites, rapid desorption of the linearly adsorbed CO species governed the performance of the Pt/MnO in the RWGS., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Ternary Pd-In 2 O 3 /ZrO 2 catalysts exhibit technological potential for CO 2 -based methanol synthesis, but developing scalable systems and comprehending complex dynamic behaviors of the active phase, promoter, and carrier are key for achieving high productivity. Here, we show that the structure of Pd-In 2 O 3 /ZrO 2 systems prepared by wet impregnation evolves under CO 2 hydrogenation conditions into a selective and stable architecture, independent of the order of addition of Pd and In phases on the zirconia carrier. Detailed operando characterization and simulations reveal a rapid restructuring driven by the metal-metal oxide interaction energetics. The proximity of InPd x alloy particles decorated by InO x layers in the resulting architecture prevents performance losses associated with Pd sintering. The findings highlight the crucial role of reaction-induced restructuring in complex CO 2 hydrogenation catalysts and offer insights into the optimal integration of acid-base and redox functions for practical implementation., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)