TY - JOUR
T1 - Acetate and phosphate anion adsorption linear sweep voltammograms simulated using density functional theory
AU - Savizi, Iman Shahidi Pour
AU - Janik, Michael J.
N1 - KAUST Repository Item: Exported on 2020-10-01
Acknowledged KAUST grant number(s): KUS-I1-003-13
Acknowledgements: This research was supported by the King Abdullah University of Science and Technology (KAUST) (Award KUS-I1-003-13).
This publication acknowledges KAUST support, but has no KAUST affiliated authors.
PY - 2011/4
Y1 - 2011/4
N2 - Specific adsorption of anions to electrode surfaces may alter the rates of electrocatalytic reactions. Density functional theory (DFT) methods are used to predict the adsorption free energy of acetate and phosphate anions as a function of Pt(1 1 1) electrode potential. Four models of the electrode potential are used including a simple vacuum slab model, an applied electric field model with and without the inclusion of a solvating water bi-layer, and the double reference model. The linear sweep voltammogram (LSV) due to anion adsorption is simulated using the DFT results. The inclusion of solvation at the electrochemical interface is necessary for accurately predicting the adsorption peak position. The Langmuir model is sufficient for predicting the adsorption peak shape, indicating coverage effects are minor in altering the LSV for acetate and phosphate adsorption. Anion adsorption peak positions are determined for solution phase anion concentrations present in microbial fuel cells and microbial electrolysis cells and discussion is provided as to the impact of anion adsorption on oxygen reduction and hydrogen evolution reaction rates in these devices. © 2011 Elsevier Ltd. All rights reserved.
AB - Specific adsorption of anions to electrode surfaces may alter the rates of electrocatalytic reactions. Density functional theory (DFT) methods are used to predict the adsorption free energy of acetate and phosphate anions as a function of Pt(1 1 1) electrode potential. Four models of the electrode potential are used including a simple vacuum slab model, an applied electric field model with and without the inclusion of a solvating water bi-layer, and the double reference model. The linear sweep voltammogram (LSV) due to anion adsorption is simulated using the DFT results. The inclusion of solvation at the electrochemical interface is necessary for accurately predicting the adsorption peak position. The Langmuir model is sufficient for predicting the adsorption peak shape, indicating coverage effects are minor in altering the LSV for acetate and phosphate adsorption. Anion adsorption peak positions are determined for solution phase anion concentrations present in microbial fuel cells and microbial electrolysis cells and discussion is provided as to the impact of anion adsorption on oxygen reduction and hydrogen evolution reaction rates in these devices. © 2011 Elsevier Ltd. All rights reserved.
UR - http://hdl.handle.net/10754/597446
UR - https://linkinghub.elsevier.com/retrieve/pii/S0013468611002234
UR - http://www.scopus.com/inward/record.url?scp=79954582130&partnerID=8YFLogxK
U2 - 10.1016/j.electacta.2011.02.013
DO - 10.1016/j.electacta.2011.02.013
M3 - Article
SN - 0013-4686
VL - 56
SP - 3996
EP - 4006
JO - Electrochimica Acta
JF - Electrochimica Acta
IS - 11
ER -