Ab Initio Approaches to Modeling Electrode Reactions

Kuznetsov and Lorenz were the first to apply ab initio quantum-chemical methods to study one of the most elementary reactions in electrochemistry, the hydrogen evolution reaction. Using SCF-HF calculations they computed potential energy surfaces for the approach of a hydrogen from a solvated hydronium (i. e. H30(H20)2) to 

Anderson and co-workers used similar extensive ab initio DFT-GGA electronic structure calculations to study an equally important electrochemical reaction, namely oxygen reduction. The oxygen reduction was supposed to take place in the following four electron transfer steps  

Erom this type of calculation, Anderson and Albu found that the activation energies for reactions 21-24 decrease in the order (23)  

Anderson et al used a similar approach based on ab initio SCF-HF MP2 theory to study the formation of surface-bonded OH and O from water on one- and two-atom Pt electrode models. They conclude that OH will not be formed by the dissociation of water into surface-bonded OH and H, but rather by a transfer of the releasing proton to 

The formation of surface-bonded OH is of great interest for another important electrocatalytic process, namely the oxidation of CO. It is usually assumed by experimentalists that the surface-bonded OH reacts with CO to form CO2 in the reaction scheme  

Desai and Neurock ° studied the mechanism of CO oxidation on PtRu in the absence and presence of water molecules using DFT-GGA slab calculations. The computational setup was similar to that used in their simulations of the water dissociation, hi the vapor phase, they calculate the reaction CO. + OH,j CO2 +, with CO on Pt and 

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