TY - JOUR
T1 - Dramatic increase in the oxygen reduction reaction for platinum cathodes from tuning the solvent dielectric constant
AU - Fortunelli, Alessandro
AU - Goddard, William A.
AU - Sha, Yao
AU - Yu, Ted H.
AU - Sementa, Luca
AU - Barcaro, Giovanni
AU - Andreussi, Oliviero
PY - 2014/6/23
Y1 - 2014/6/23
N2 - Hydrogen fuel cells (FC) are considered essential for a sustainable economy based on carbon-free energy sources, but a major impediment are the costs. First-principles quantum mechanics (density functional theory including solvation) is used to predict how the energies and barriers for the mechanistic steps of the oxygen reduction reaction (ORR) over the fcc(111) platinum surface depend on the dielectric constant of the solvent. The ORR kinetics can be strongly accelerated by decreasing the effective medium polarizability from the high value it has in water. Possible ways to realize this experimentally are suggested. The calculated volcano structure for the dependence of rate on solvent polarization is considered to be general, and should be observed in other electrochemical systems. Hydrogen fuel cell: The oxygen reduction reaction (ORR) kinetics can be strongly accelerated by changing the solvent and its dielectric constant, a possibly general effect in electrochemical systems. The influence of the solvent dielectric constant on the reaction barriers of the ORR is studied by density functional theory (see picture).
AB - Hydrogen fuel cells (FC) are considered essential for a sustainable economy based on carbon-free energy sources, but a major impediment are the costs. First-principles quantum mechanics (density functional theory including solvation) is used to predict how the energies and barriers for the mechanistic steps of the oxygen reduction reaction (ORR) over the fcc(111) platinum surface depend on the dielectric constant of the solvent. The ORR kinetics can be strongly accelerated by decreasing the effective medium polarizability from the high value it has in water. Possible ways to realize this experimentally are suggested. The calculated volcano structure for the dependence of rate on solvent polarization is considered to be general, and should be observed in other electrochemical systems. Hydrogen fuel cell: The oxygen reduction reaction (ORR) kinetics can be strongly accelerated by changing the solvent and its dielectric constant, a possibly general effect in electrochemical systems. The influence of the solvent dielectric constant on the reaction barriers of the ORR is studied by density functional theory (see picture).
KW - density functional calculations
KW - electrochemistry
KW - hydrogen fuel cells
KW - reaction energy barriers
KW - solvation
UR - http://www.scopus.com/inward/record.url?scp=84903119232&partnerID=8YFLogxK
U2 - 10.1002/anie.201403264
DO - 10.1002/anie.201403264
M3 - Article
AN - SCOPUS:84903119232
SN - 1433-7851
VL - 53
SP - 6669
EP - 6672
JO - Angewandte Chemie - International Edition
JF - Angewandte Chemie - International Edition
IS - 26
ER -