scholarly journals Computational Scaling Relationships Predict Experimental Activity and Rate Limiting Behavior in Homogenous Water Oxidation

Author(s):  
Heather Kulik ◽  
Daniel Harper
2018 ◽  
Vol 6 (47) ◽  
pp. 24358-24366 ◽  
Author(s):  
Hao Li ◽  
Huan Shang ◽  
Yuchen Shi ◽  
Rositsa Yakimova ◽  
Mikael Syväjärvi ◽  
...  

Preferential exposure of Si-face of SiC will mechanistically shift the rate limiting step of water oxidation from sluggish proton-coupled electron transfer on C-face to a more energy-favorable electron transfer.


2017 ◽  
Vol 23 (65) ◽  
pp. 16413-16418 ◽  
Author(s):  
Joeri Hessels ◽  
Remko J. Detz ◽  
Marc T. M. Koper ◽  
Joost N. H. Reek

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Laia Francàs ◽  
Sacha Corby ◽  
Shababa Selim ◽  
Dongho Lee ◽  
Camilo A. Mesa ◽  
...  

AbstractNi/Fe oxyhydroxides are the best performing Earth-abundant electrocatalysts for water oxidation. However, the origin of their remarkable performance is not well understood. Herein, we employ spectroelectrochemical techniques to analyse the kinetics of water oxidation on a series of Ni/Fe oxyhydroxide films: FeOOH, FeOOHNiOOH, and Ni(Fe)OOH (5% Fe). The concentrations and reaction rates of the oxidised states accumulated during catalysis are determined. Ni(Fe)OOH is found to exhibit the fastest reaction kinetics but accumulates fewer states, resulting in a similar performance to FeOOHNiOOH. The later catalytic onset in FeOOH is attributed to an anodic shift in the accumulation of oxidised states. Rate law analyses reveal that the rate limiting step for each catalyst involves the accumulation of four oxidised states, Ni-centred for Ni(Fe)OOH but Fe-centred for FeOOH and FeOOHNiOOH. We conclude by highlighting the importance of equilibria between these accumulated species and reactive intermediates in determining the activity of these materials.


2014 ◽  
Vol 136 (34) ◽  
pp. 11938-11945 ◽  
Author(s):  
Yulia Pushkar ◽  
Dooshaye Moonshiram ◽  
Vatsal Purohit ◽  
Lifen Yan ◽  
Igor Alperovich

2021 ◽  
Author(s):  
Emily Mazeau ◽  
Priyanka Satpute ◽  
Katrin Blondal ◽  
Franklin Goldsmith ◽  
Richard West

<div>Kinetic parameters for surface reactions can be predicted using a combination of DFT calculations, scaling relations, and machine learning algorithms; however, construction of microkinetic models still requires a knowledge of all the possible, or at least reasonable, reaction pathways. The recently developed Reaction Mechanism Generator (RMG) for heterogeneous catalysis, now included in RMG version 3.0, is built upon well-established, open-source software that can provide detailed reaction mechanisms from user-supplied initial conditions without making <i>a priori</i> assumptions. RMG is now able to estimate adsorbate thermochemistry and construct detailed microkinetic models on a range of hypothetical metal surfaces using linear scaling relationships. These relationships are a simple, computationally efficient way to estimate adsorption energies by scaling the energy of a calculated surface species on one metal to any other metal. By conducting simulations with sensitivity analyses, users can not only determine the rate limiting step on each surface by plotting a "volcano surface" for the degree of rate control of each reaction as a function of elemental binding energies, but also screen novel catalysts for desirable properties. We investigated the catalytic partial oxidation of methane to demonstrate the utility of this new tool and determined that an inlet gas C/O ratio of 0.8 on a catalyst with carbon and oxygen binding energies of -6.75 eV and -5.0 eV, respectively, yields the highest amount of synthesis gas. Sensitivity analyses show that while the dissociative adsorption of O<sub>2</sub> has the highest degree of rate control, the interactions between individual reactions and reactor conditions are complex, which result in a dynamic rate-limiting step across differing metals.</div>


2021 ◽  
Author(s):  
Emily Mazeau ◽  
Priyanka Satpute ◽  
Katrin Blondal ◽  
Franklin Goldsmith ◽  
Richard West

<div>Kinetic parameters for surface reactions can be predicted using a combination of DFT calculations, scaling relations, and machine learning algorithms; however, construction of microkinetic models still requires a knowledge of all the possible, or at least reasonable, reaction pathways. The recently developed Reaction Mechanism Generator (RMG) for heterogeneous catalysis, now included in RMG version 3.0, is built upon well-established, open-source software that can provide detailed reaction mechanisms from user-supplied initial conditions without making <i>a priori</i> assumptions. RMG is now able to estimate adsorbate thermochemistry and construct detailed microkinetic models on a range of hypothetical metal surfaces using linear scaling relationships. These relationships are a simple, computationally efficient way to estimate adsorption energies by scaling the energy of a calculated surface species on one metal to any other metal. By conducting simulations with sensitivity analyses, users can not only determine the rate limiting step on each surface by plotting a "volcano surface" for the degree of rate control of each reaction as a function of elemental binding energies, but also screen novel catalysts for desirable properties. We investigated the catalytic partial oxidation of methane to demonstrate the utility of this new tool and determined that an inlet gas C/O ratio of 0.8 on a catalyst with carbon and oxygen binding energies of -6.75 eV and -5.0 eV, respectively, yields the highest amount of synthesis gas. Sensitivity analyses show that while the dissociative adsorption of O<sub>2</sub> has the highest degree of rate control, the interactions between individual reactions and reactor conditions are complex, which result in a dynamic rate-limiting step across differing metals.</div>


2018 ◽  
Vol 140 (9) ◽  
pp. 3264-3269 ◽  
Author(s):  
Yuchao Zhang ◽  
Hongna Zhang ◽  
Anan Liu ◽  
Chuncheng Chen ◽  
Wenjing Song ◽  
...  

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