Computational modelling of water oxidation catalysts

Soriano-López, Joaquín; Schmitt, Wolfgang; García‐Melchor, Max

doi:10.1016/j.coelec.2017.10.001

Cited by 49 publications

(44 citation statements)

References 68 publications

(69 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…During the last decade, computational electrochemistry has been demonstrated to be a useful tool in the effort to understand the intermediate steps of electrochemical processes and the reaction mechanisms involved . Moreover, through the identification of significant descriptors, it has become possible to provide a classification of promising and poor electrocatalysts, as well as to indicate the way towards their improvement.…”

Section: Introductionmentioning

confidence: 99%

Computational Electrochemistry of Water Oxidation on Metal‐Doped and Metal‐Supported Defective h‐BN

et al. 2019

View full text Add to dashboard Cite

Metal‐doped and metal‐supported two‐dimensional materials are attracting a lot of interest as potentially active electrocatalysts for reduction and oxidation processes. Previously, when a non‐regular 2 D h‐BN layer was grown on a Cu(111) surface, metal adatoms were found to spontaneously emerge from the bulk to fill the atomic holes in the structure and become available for surface catalysis. Herein, computational electrochemistry is used to investigate and compare the performance of Cu‐doped and Cu‐supported pristine and defective h‐BN systems for the electrocatalytic water oxidation reaction. For the various model systems, the intermediate species of this multistep oxidation process are identified and the free‐energy variations for each step of reaction are computed, even for those steps that do not involve an electron or a proton transfer. Both associative and O2 direct evolution mechanisms are considered. On this thermodynamic basis, the potential‐determining step, the thermodynamic‐determining step, and consequently the theoretical overpotential are determined for comparison with experiments. Small Cu clusters (tetramers) trapped in the h‐BN defective lattice on a Cu(111) support are found to be very active for the water oxidation reaction since such systems are characterized by a low overpotential and by a small energy cost for O2 release from the catalyst, which is often observed to be a major limit for other potential electrocatalysts.

show abstract

Section: Introductionmentioning

confidence: 99%

Computational Electrochemistry of Water Oxidation on Metal‐Doped and Metal‐Supported Defective h‐BN

et al. 2019

View full text Add to dashboard Cite

show abstract

“…The two primary pathways proposed for the O-O bond formation are the water nucleophilic attack (WNA) and the interaction of two metal-oxo entities (I2M), as depicted in Fig. 1 9 . Both reaction paths begin with two proton electron transfer (PET) events 10 , giving rise to a metal-oxo intermediate.…”

mentioning

confidence: 99%

“…Another major implication of the above OER scaling is that since ΔG 1 and ΔG 4 are rarely PLS, the Gibbs energy difference between the O Ã and HO Ã intermediates (ΔG O Ã − ΔG HO Ã ) can be employed as a reaction descriptor to predict the OER activity of heterogeneous catalysts 9,22 . In fact, this descriptor has been successfully applied to rationalize the activity of a wide variety of metal oxide and single-atom electrocatalysts, wherein the most active ones exhibit a descriptor which is close to the optimal value predicted by the scaling relations, i.e.…”

mentioning

confidence: 99%

Universal scaling relations for the rational design of molecular water oxidation catalysts with near-zero overpotential

et al. 2019

Self Cite

View full text Add to dashboard Cite

A major roadblock in realizing large-scale production of hydrogen via electrochemical water splitting is the cost and inefficiency of current catalysts for the oxygen evolution reaction (OER). Computational research has driven important developments in understanding and designing heterogeneous OER catalysts using linear scaling relationships derived from computed binding energies. Herein, we interrogate 17 of the most active molecular OER catalysts, based on different transition metals (Ru, Mn, Fe, Co, Ni, and Cu), and show they obey similar scaling relations to those established for heterogeneous systems. However, we find that the conventional OER descriptor underestimates the activity for very active OER complexes as the standard approach neglects a crucial one-electron oxidation that many molecular catalysts undergo prior to O-O bond formation. Importantly, this additional step allows certain molecular catalysts to circumvent the "overpotential wall", leading to enhanced performance. With this knowledge, we establish fundamental principles for the design of ideal molecular OER catalysts.

show abstract

“…23 [15][16][17][18][19][20] Another major implication of the above OER scaling is that since ∆ G and ∆ Q are rarely PLS, the Gibbs energy difference between the O* and HO* intermediates (∆G j * − ∆G kj * ) can be employed as a reaction descriptor to predict the OER activity of heterogeneous catalysts. 9,21 In fact, this descriptor has been successfully applied to rationalize the activity of a wide variety of metal oxide and single-atom electrocatalysts, wherein the most active ones exhibit a descriptor which is close to the optimal value predicted by the scaling relations, i.e. 3.2/2 = 1.6 eV.…”

mentioning

confidence: 97%

“…The two primary pathways proposed for the O-O bond formation are the water nucleophilic attack (WNA) and the interaction of two metal-oxo entities (I2M), as depicted in Scheme 1. 9 Both reaction paths begin with two proton electron transfer (PET) events 10 giving rise to a metal-oxo intermediate. In the case of WNA, this metal-oxo species subsequently undergoes the nucleophilic attack of a solvent water molecule and a further PET to generate the O-O bond, whereas in the I2M mechanism the O-O bond formation involves the coupling of two separate metal-oxo moieties.…”

mentioning

confidence: 99%

Universal Scaling Relations for the Rational Design of Molecular Water Oxidation Catalysts with Near- Zero Overpotential

Craig¹,

Coulter²,

dolan³

et al. 2019

Preprint

Self Cite

View full text Add to dashboard Cite

<div><div><div><p>A major roadblock in realizing the large-scale production of hydrogen via electrochemical water splitting is the lack of cost-effective and highly efficient catalysts for the oxygen evolution reaction (OER). In this regard, computational research has driven important developments in the understanding and the design of heterogeneous OER catalysts by establishing linear scaling relations. These relations are of paramount importance since they drastically reduce the amount of time required to traverse the vast chemical search space of potential OER materials. In this work, we interrogate 17 of the most active molecular OER catalysts known to date based on different transition metals (M= Ru, Mn, Fe, Co, Ni, and Cu), and show that they obey the linear scaling relations established for metal oxides. This demonstrates that the conventional OER descriptor established for heterogeneous systems can also be applied to rapidly screen novel molecular catalysts. However, we find that this descriptor underestimates the activity of some of the most active OER complexes as it does not consider the additional one-electron oxidation that these undergo prior to O–O bond formation. Importantly, we show that this additional step allows certain molecular catalysts to circumvent the “overpotential wall” observed for heterogeneous systems (i.e. 370 mV), leading to an enhanced performance in agreement with experimental observations. To describe the activity of such highly active catalysts, we propose a new OER descriptor that opens up the possibility of designing molecular catalysts exhibiting zero theoretical overpotential. With all this knowledge, we establish the fundamental principles for the rational design of ideal OER catalysts to advance the development of water splitting technologies.</p></div></div></div>

show abstract

Computational modelling of water oxidation catalysts

Cited by 49 publications

References 68 publications

Computational Electrochemistry of Water Oxidation on Metal‐Doped and Metal‐Supported Defective h‐BN

Computational Electrochemistry of Water Oxidation on Metal‐Doped and Metal‐Supported Defective h‐BN

Universal scaling relations for the rational design of molecular water oxidation catalysts with near-zero overpotential

Universal Scaling Relations for the Rational Design of Molecular Water Oxidation Catalysts with Near- Zero Overpotential

Contact Info

Product

Resources

About