TY - JOUR
T1 - Stark effect or coverage dependence? Disentangling the EC-SEIRAS vibrational shift of sulfate on Au(111)
AU - Pfisterer, Jonas H.K.
AU - Zhumaev, Ulmas E.
AU - Cheuquepan, William
AU - Feliu, Juan M.
AU - Domke, Katrin F.
N1 - Publisher Copyright:
© 2019 Author(s).
PY - 2019/1/28
Y1 - 2019/1/28
N2 - Infrared spectroscopy is a widely employed analytical tool in (electrochemical) surface science as the spectra contain a wealth of information about the interaction of interfacial adsorbates with their environment. Separating and quantifying individual contributions, for example, of co-adsorbates, the substrate or electric field effects, on the overall spectral response, however, is often non-trivial as the various interactions manifest themselves in similar spectral behavior. Here, we present an experimental approach to differentiate between and quantify potential-induced coverage dependence and field-related Stark effects observed in a sulfate band shift of 93.5 ± 1.5 cm-1/V in electrochemical infrared spectra of the showcase sulfate/Au(111) interface. In combination with a simple linear model equation used to describe the potential-induced peak shift of the sulfate stretch vibration, we determine the coverage dependence contribution to be 15.6 ± 1.2 cm-1/θSO and the Stark effect to amount to 75.6 ± 2.7 cm-1/V. Our work provides a novel route to gain fundamental insight into interfacial adsorbate interactions in electrochemical surface science.
AB - Infrared spectroscopy is a widely employed analytical tool in (electrochemical) surface science as the spectra contain a wealth of information about the interaction of interfacial adsorbates with their environment. Separating and quantifying individual contributions, for example, of co-adsorbates, the substrate or electric field effects, on the overall spectral response, however, is often non-trivial as the various interactions manifest themselves in similar spectral behavior. Here, we present an experimental approach to differentiate between and quantify potential-induced coverage dependence and field-related Stark effects observed in a sulfate band shift of 93.5 ± 1.5 cm-1/V in electrochemical infrared spectra of the showcase sulfate/Au(111) interface. In combination with a simple linear model equation used to describe the potential-induced peak shift of the sulfate stretch vibration, we determine the coverage dependence contribution to be 15.6 ± 1.2 cm-1/θSO and the Stark effect to amount to 75.6 ± 2.7 cm-1/V. Our work provides a novel route to gain fundamental insight into interfacial adsorbate interactions in electrochemical surface science.
UR - http://www.scopus.com/inward/record.url?scp=85058104540&partnerID=8YFLogxK
U2 - 10.1063/1.5047941
DO - 10.1063/1.5047941
M3 - Article
C2 - 30709299
AN - SCOPUS:85058104540
SN - 0021-9606
VL - 150
SP - 041709
JO - Journal of Chemical Physics
JF - Journal of Chemical Physics
IS - 4
M1 - 5047941
ER -