Synergetic effects of edge formation and sulfur doping on the catalytic activity of a graphene-based catalyst for the oxygen reduction reaction

To facilitate the rational design of alloy catalysts, we introduce a method for rapidly calculating the structure and catalytic properties of a substitutional alloy surface that is in equilibrium with the underlying bulk phase. We implement our method by developing a way to generate surface cluster expansions that explicitly account for the lattice parameter of the bulk structure. This approach makes it possible to computationally map the structure of an alloy surface and statistically sample adsorbate binding energies at every point in the alloy phase diagram. When combined with a method for predicting catalytic activities from adsorbate binding energies, maps of catalytic activities at every point in the phase diagram can be created, enabling the identification of synthesis conditions likely to result in highly active catalysts. We demonstrate our approach by analyzing Pt-rich Pt–Ni catalysts for the oxygen reduction reaction, finding two regions in the phase diagram that are predicted to result in highly active catalysts. Our analysis indicates that the Pt3Ni(111) surface, which has the highest known specific activity for the oxygen reduction reaction, is likely able to achieve its high activity through the formation of an intermetallic phase with L12 order. We use the generated surface structure and catalytic activity maps to demonstrate how the intermetallic nature of this phase leads to high catalytic activity and discuss how the underlying principles can be used in catalysis design. We further discuss the importance of surface phases and demonstrate how they can dramatically affect catalytic activity.

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Computationally Generated Maps of Surface Structures and Catalytic Activities for Alloy Phase Diagrams

10.26434/chemrxiv.8311865 ◽

2019 ◽

Author(s):

Liang Cao ◽

Le, Niu ◽

Tim Mueller

Keyword(s):

Phase Diagram ◽

Catalytic Activity ◽

Oxygen Reduction Reaction ◽

Oxygen Reduction ◽

Reduction Reaction ◽

Binding Energies ◽

Alloy Surface ◽

High Catalytic Activity ◽

Catalytic Activities ◽

Highly Active

To facilitate the rational design of alloy catalysts, we introduce a method for rapidly calculating the structure and catalytic properties of a substitutional alloy surface that is in equilibrium with the underlying bulk phase. We implement our method by developing a way to generate surface cluster expansions that explicitly account for the lattice parameter of the bulk structure. This approach makes it possible to computationally map the structure of an alloy surface and statistically sample adsorbate binding energies at every point in the alloy phase diagram. When combined with a method for predicting catalytic activities from adsorbate binding energies, maps of catalytic activities at every point in the phase diagram can be created, enabling the identification of synthesis conditions likely to result in highly active catalysts. We demonstrate our approach by analyzing Pt-rich Pt–Ni catalysts for the oxygen reduction reaction, finding two regions in the phase diagram that are predicted to result in highly active catalysts. Our analysis indicates that the Pt3Ni(111) surface, which has the highest known specific activity for the oxygen reduction reaction, is likely able to achieve its high activity through the formation of an intermetallic phase with L12 order. We use the generated surface structure and catalytic activity maps to demonstrate how the intermetallic nature of this phase leads to high catalytic activity and discuss how the underlying principles can be used in catalysis design. We further discuss the importance of surface phases and demonstrate how they can dramatically affect catalytic activity.

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Computationally Generated Maps of Surface Structures and Catalytic Activities for Alloy Phase Diagrams

10.26434/chemrxiv.8311865.v1 ◽

2019 ◽

Author(s):

Liang Cao ◽

Le, Niu ◽

Tim Mueller

Keyword(s):

Phase Diagram ◽

Catalytic Activity ◽

Oxygen Reduction Reaction ◽

Oxygen Reduction ◽

Rational Design ◽

Intermetallic Phase ◽

Reduction Reaction ◽

Alloy Surface ◽

High Catalytic Activity ◽

Highly Active

To facilitate the rational design of alloy catalysts, we introduce a method for rapidly calculating the structure and catalytic properties of a substitutional alloy surface that is in equilibrium with the underlying bulk phase. We implement our method by developing a way to generate surface cluster expansions that explicitly account for the lattice parameter of the bulk structure. This approach makes it possible to computationally map the structure and catalytic activity of an alloy surface at every point in the alloy phase diagram, enabling the identification of synthesis conditions likely to result in highly active catalysts. We demonstrate our approach by analyzing Pt-rich Pt–Ni catalysts for the oxygen reduction reaction, finding two regions in the phase diagram that are predicted to result in highly active catalysts. Our analysis indicates that the Pt3Ni(111) surface, which has the highest known specific activity for the oxygen reduction reaction, is likely able to achieve its high activity through the formation of an intermetallic phase with L12 order. We use the generated surface structure and catalytic activity maps to demonstrate how the intermetallic nature of this phase leads to high catalytic activity and discuss how the underlying principles can be used in catalysis design. We further discuss the importance of surface phases and demonstrate how they can dramatically affect catalytic activity.

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Computationally generated maps of surface structures and catalytic activities for alloy phase diagrams

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1910724116 ◽

2019 ◽

Vol 116 (44) ◽

pp. 22044-22051 ◽

Cited By ~ 1

Author(s):

Liang Cao ◽

Le Niu ◽

Tim Mueller

Keyword(s):

Phase Diagram ◽

Catalytic Activity ◽

Oxygen Reduction Reaction ◽

Oxygen Reduction ◽

Reduction Reaction ◽

Binding Energies ◽

Alloy Surface ◽

High Catalytic Activity ◽

Catalytic Activities ◽

Highly Active

To facilitate the rational design of alloy catalysts, we introduce a method for rapidly calculating the structure and catalytic properties of a substitutional alloy surface that is in equilibrium with the underlying bulk phase. We implement our method by developing a way to generate surface cluster expansions that explicitly account for the lattice parameter of the bulk structure. This approach makes it possible to computationally map the structure of an alloy surface and statistically sample adsorbate binding energies at every point in the alloy phase diagram. When combined with a method for predicting catalytic activities from adsorbate binding energies, maps of catalytic activities at every point in the phase diagram can be created, enabling the identification of synthesis conditions likely to result in highly active catalysts. We demonstrate our approach by analyzing Pt-rich Pt–Ni catalysts for the oxygen reduction reaction, finding 2 regions in the phase diagram that are predicted to result in highly active catalysts. Our analysis indicates that the Pt3Ni(111) surface, which has the highest known specific activity for the oxygen reduction reaction, is likely able to achieve its high activity through the formation of an intermetallic phase with L12 order. We use the generated surface structure and catalytic activity maps to demonstrate how the intermetallic nature of this phase leads to high catalytic activity and discuss how the underlying principles can be used in catalysis design. We further discuss the importance of surface phases and demonstrate how they can dramatically affect catalytic activity.

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Computationally Generated Maps of Surface Structures and Catalytic Activities for Alloy Phase Diagrams

10.26434/chemrxiv.8311865.v2 ◽

2019 ◽

Author(s):

Liang Cao ◽

Le, Niu ◽

Tim Mueller

Keyword(s):

Phase Diagram ◽

Catalytic Activity ◽

Oxygen Reduction Reaction ◽

Oxygen Reduction ◽

Rational Design ◽

Intermetallic Phase ◽

Reduction Reaction ◽

Alloy Surface ◽

High Catalytic Activity ◽

Highly Active

To facilitate the rational design of alloy catalysts, we introduce a method for rapidly calculating the structure and catalytic properties of a substitutional alloy surface that is in equilibrium with the underlying bulk phase. We implement our method by developing a way to generate surface cluster expansions that explicitly account for the lattice parameter of the bulk structure. This approach makes it possible to computationally map the structure and catalytic activity of an alloy surface at every point in the alloy phase diagram, enabling the identification of synthesis conditions likely to result in highly active catalysts. We demonstrate our approach by analyzing Pt-rich Pt–Ni catalysts for the oxygen reduction reaction, finding two regions in the phase diagram that are predicted to result in highly active catalysts. Our analysis indicates that the Pt3Ni(111) surface, which has the highest known specific activity for the oxygen reduction reaction, is likely able to achieve its high activity through the formation of an intermetallic phase with L12 order. We use the generated surface structure and catalytic activity maps to demonstrate how the intermetallic nature of this phase leads to high catalytic activity and discuss how the underlying principles can be used in catalysis design. We further discuss the importance of surface phases and demonstrate how they can dramatically affect catalytic activity.

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Fabrication of Non-precious Vanadium Tungsten Nanocomposite for Enhanced Electrocatalytic Oxygen Reduction Reaction

Asian Journal of Chemistry ◽

10.14233/ajchem.2021.23097 ◽

2021 ◽

Vol 33 (4) ◽

pp. 919-924

Author(s):

L. Stanlykeninxavier ◽

P. Elangovan ◽

M.S.S. Saravanakumaar

Keyword(s):

Catalytic Activity ◽

Oxygen Reduction Reaction ◽

Oxygen Reduction ◽

High Performance ◽

High Efficiency ◽

Low Cost ◽

High Capacity ◽

Reduction Reaction ◽

Highly Active ◽

Electrocatalytic Oxygen Reduction

For the commercialization of alkaline fuel cells and metal air batteries, the advances in non-precious, cheap, stable electrocatalysts for the oxygen reduction reaction (ORR) and highly active remain a major problem. To overcome this problem, a facile approach was established to fabricate non-precious metal electrocatalysts, such as nanoparticles, pristine V2O5 and their WO3 hybrids. This is the first study reporting the utilization of monoclinic-WO3-nanocrystal-coupled V2O5 that serves as ORR catalysts. Compared with 50 wt.% WO3 with 50 wt.% V2O5 (VW-2) spheres and pristine V2O5, the hybrid catalyst of 25 wt.% WO3 and 75 wt.% V2O5 (VW-1) spheres exhibits outstanding catalytic activity towards ORR. In addition, the hybrid of 25 wt.% WO3 and 75 wt.% V2O5 (VW-1) exhibits a higher long-term durability and catalytic activity than high-quality commercial Pt/C catalysts, which renders the composites of WO3/V2O5 composites hybrid a high-capacity candidate for non-precious, high-performance, metal-based electrocatalysts having high efficiency and low cost for electrochemical energy conversion. The enhanced activity of WO3/V2O5 composites is mainly obtained from the improved structural openness in the V2O5 tunnel structure when coupled with WO3.

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