Rensselaer Polytechnic Inst., Troy, NY (United States); California Inst. of Technology (CalTech), Pasadena, CA (United States); California Institute of Technology
California Inst. of Technology (CalTech), Pasadena, CA (United States)
First-principles calculations combining density-functional theory and continuum solvation models enable realistic theoretical modeling and design of electrochemical systems. When a reaction proceeds in such systems, the number of electrons in the portion of the system treated quantum mechanically changes continuously, with a balancing charge appearing in the continuum electrolyte. A grand-canonical ensemble of electrons at a chemical potential set by the electrode potential is therefore the ideal description of such systems that directly mimics the experimental condition. We present two distinct algorithms: a self-consistent field method and a direct variational free energy minimization method using auxiliary Hamiltonians (GC-AuxH), to solve the Kohn-Sham equations of electronic density-functional theory directly in the grand canonical ensemble at fixed potential. Both methods substantially improve performance compared to a sequence of conventional fixed-number calculations targeting the desired potential, with the GC-AuxH method additionally exhibiting reliable and smooth exponential convergence of the grand free energy. Lastly, we apply grand-canonical density-functional theory to the under-potential deposition of copper on platinum from chloride-containing electrolytes and show that chloride desorption, not partial copper monolayer formation, is responsible for the second voltammetric peak.
Sundararaman, Ravishankar, et al. "Grand canonical electronic density-functional theory: Algorithms and applications to electrochemistry." Journal of Chemical Physics, vol. 146, no. 11, Mar. 2017. https://doi.org/10.1063/1.4978411
Sundararaman, Ravishankar, Goddard, III, William A., & Arias, Tomas A. (2017). Grand canonical electronic density-functional theory: Algorithms and applications to electrochemistry. Journal of Chemical Physics, 146(11). https://doi.org/10.1063/1.4978411
Sundararaman, Ravishankar, Goddard, III, William A., and Arias, Tomas A., "Grand canonical electronic density-functional theory: Algorithms and applications to electrochemistry," Journal of Chemical Physics 146, no. 11 (2017), https://doi.org/10.1063/1.4978411
@article{osti_1347429,
author = {Sundararaman, Ravishankar and Goddard, III, William A. and Arias, Tomas A.},
title = {Grand canonical electronic density-functional theory: Algorithms and applications to electrochemistry},
annote = {First-principles calculations combining density-functional theory and continuum solvation models enable realistic theoretical modeling and design of electrochemical systems. When a reaction proceeds in such systems, the number of electrons in the portion of the system treated quantum mechanically changes continuously, with a balancing charge appearing in the continuum electrolyte. A grand-canonical ensemble of electrons at a chemical potential set by the electrode potential is therefore the ideal description of such systems that directly mimics the experimental condition. We present two distinct algorithms: a self-consistent field method and a direct variational free energy minimization method using auxiliary Hamiltonians (GC-AuxH), to solve the Kohn-Sham equations of electronic density-functional theory directly in the grand canonical ensemble at fixed potential. Both methods substantially improve performance compared to a sequence of conventional fixed-number calculations targeting the desired potential, with the GC-AuxH method additionally exhibiting reliable and smooth exponential convergence of the grand free energy. Lastly, we apply grand-canonical density-functional theory to the under-potential deposition of copper on platinum from chloride-containing electrolytes and show that chloride desorption, not partial copper monolayer formation, is responsible for the second voltammetric peak.},
doi = {10.1063/1.4978411},
url = {https://www.osti.gov/biblio/1347429},
journal = {Journal of Chemical Physics},
issn = {ISSN 0021-9606},
number = {11},
volume = {146},
place = {United States},
publisher = {American Institute of Physics (AIP)},
year = {2017},
month = {03}}
California Inst. of Technology (CalTech), Pasadena, CA (United States); California Institute of Technology, Pasadena, CA (United States); Energy Frontier Research Centers (EFRC) (United States). Energy Materials Center at Cornell (EMC2)
Sponsoring Organization:
USDOE; USDOE Office of Energy Efficiency and Renewable Energy (EERE); USDOE Office of Science (SC); USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
Grant/Contract Number:
AC02-05CH11231; SC0001086; SC0004993
OSTI ID:
1347429
Alternate ID(s):
OSTI ID: 1348036 OSTI ID: 1467630
Journal Information:
Journal of Chemical Physics, Journal Name: Journal of Chemical Physics Journal Issue: 11 Vol. 146; ISSN 0021-9606