In situ linear optical diffraction is a new method for studies of surface mass transport in electrochemical environments that is based on the equilibration of coverage gratings in an adlayer on the electrode surface. We, here, discuss the temporal evolution of the diffraction intensity on the basis of experimental data for sulfur adsorbates on Pt(111) electrodes in 0.1M H2SO4 and simulations of the time-dependent diffusion profiles. At low and medium sulfur coverage, the decay of the signal exhibits two time scales, which can be explained by the influence of coverage-dependent diffusion rates on the evolution of gratings with large coverage modulation. At high coverage, a further ultra-slow decay process or even a complete termination of the decay is observed, which we attribute to the presence of high-density, ordered, adlayer phases with low sulfur mobility. These results provide insight into the approaches required for extracting quantitative surface transport rates from linear optical diffraction measurements.

1.
Y.-E.
Sung
,
W.
Chrzanowski
,
A.
Zolfaghari
,
G.
Jerkiewicz
, and
A.
Wieckowski
, “
Structure of chemisorbed sulfur on a Pt(111) electrode
,”
J. Am. Chem. Soc.
119
,
194
200
(
1997
).
2.
E.
Protopopoff
and
P.
Marcus
, “
Effects of chemisorbed sulphur on the hydrogen adsorption and evolution on metal single crystal surfaces
,”
J. Chim. Phys.
88
,
1423
1452
(
1991
).
3.
Y.
Nagahara
,
S.
Sugawara
, and
K.
Shinohara
, “
The impact of air contaminants on PEMFC performance and durability
,”
J. Power Sources
182
,
422
428
(
2008
).
4.
V. A.
Sethuraman
and
J. W.
Weidner
, “
Analysis of sulfur poisoning on a PEM fuel cell electrode
,”
Electrochim. Acta
55
,
5683
5694
(
2010
).
5.
D. E.
Ramaker
,
D.
Gatewood
,
A.
Korovina
,
Y.
Garsany
, and
K. E.
Swider-Lyons
, “
Resolving sulfur oxidation and removal from Pt and Pt3Co electrocatalysts using in situ x-ray absorption spectroscopy
,”
J. Phys. Chem. C
114
,
11886
11897
(
2010
).
6.
P.
Jayaraj
,
P.
Karthika
,
N.
Rajalakshmi
, and
K. S.
Dhathathreyan
, “
Mitigation studies of sulfur contaminated electrodes for PEMFC
,”
Int. J. Hydrogen Energy
39
,
12045
12051
(
2014
).
7.
C.-H.
Chen
,
A.
Halford
,
M.
Walker
,
C.
Brennan
,
S. C. S.
Lai
,
D. J.
Fermin
,
P. R.
Unwin
, and
P.
Rodriguez
, “
Electrochemical characterization and regeneration of sulfur poisoned Pt catalysts in aqueous media
,”
J. Electroanal. Chem.
816
,
138
148
(
2018
).
8.
T.
Loučka
, “
Adsorption and oxidation of sulphur and of sulphur dioxide at the platinum electrode
,”
J. Electroanal. Chem. Interfacial Electrochem.
31
,
319
332
(
1971
).
9.
T.
Loučka
, “
The adsorption of sulphur and of simple organic substances on platinum electrodes
,”
J. Electroanal. Chem. Interfacial Electrochem.
36
,
369
381
(
1972
).
10.
A. Q.
Contractor
and
H.
Lal
, “
Two forms of chemisorbed sulfur on platinum and related studies
,”
J. Electroanal. Chem. Interfacial Electrochem.
96
,
175
181
(
1979
).
11.
E.
Lamy-Pitara
,
L.
Bencharif
, and
J.
Barbier
, “
Adsorption du soufre sur le platine
,”
Electrochim. Acta
30
,
971
979
(
1985
).
12.
E.
Lamy-Pitara
,
Y.
Tainon
,
B.
Beden
, and
J.
Barbier
, “
Nature and effects of sulphur adsorbed on platinum in acid medium: An investigation using UV-visible reflectance spectroscopy
,”
J. Electroanal. Chem. Interfacial Electrochem.
279
,
291
303
(
1990
).
13.
C.
Quijada
,
A.
Rodes
,
J. L.
Vázquez
,
J. M.
Pérez
, and
A.
Aldaz
, “
Electrochemical behaviour of aqueous sulphur dioxide at polycrystalline Pt electrodes in acidic medium. A voltammetric and in-situ FT-IR study Part II. Promoted oxidation of sulphur dioxide. Reduction of sulphur dioxide
,”
J. Electroanal. Chem.
398
,
105
115
(
1995
).
14.
A.
Zolfaghari
,
G.
Jerkiewicz
,
W.
Chrzanowski
, and
A.
Wieckowski
, “
Energetics of the underpotential deposition of hydrogen on platinum electrodes: II. Presence of coadsorbed sulfur
,”
J. Electrochem. Soc.
146
,
4158
4165
(
1999
).
15.
R. V.
Bucur
, “
State of the pre-adsorbed sulfur on a rough platinum electrode in voltammetric conditions: Microgravimetric measurements with electrochemical quartz crystal microbalance
,”
Electrochim. Acta
87
,
186
193
(
2013
).
16.
C.-H.
Chen
,
C.
Brennan
,
S. C. S.
Lai
,
D. J.
Fermin
,
P. R.
Unwin
, and
P.
Rodriguez
, “
Adsorption and electrochemical oxidation of small sulfur containing anions on Pt electrodes in organic media
,”
ChemElectroChem
5
,
2228
2234
(
2018
).
17.
S.
Renisch
, “
On the diffusion of adsorbed particles on single crystal surfaces: dynamical investigations with the scanning tunneling microscope
,” Ph.D. thesis,
FU Berlin
,
1999
.
18.
A. U.
Nilekar
,
J.
Greeley
, and
M.
Mavrikakis
, “
A simple rule of thumb for diffusion on transition-metal surfaces
,”
Angew. Chem., Int. Ed.
45
,
7046
(
2006
).
19.
C. R.
Bernard Rodríguez
and
J. A.
Santana
, “
Adsorption and diffusion of sulfur on the (111), (100), (110), and (211) surfaces of FCC metals: Density functional theory calculations
,”
J. Chem. Phys.
149
,
204701
(
2018
).
20.
T.
Tansel
and
O. M.
Magnussen
, “
Video STM studies of adsorbate diffusion at electrochemical interfaces
,”
Phys. Rev. Lett.
96
,
026101
(
2006
).
21.
Y.-C.
Yang
and
O. M.
Magnussen
, “
Quantitative studies of adsorbate dynamics at noble metal electrodes by in situ video-STM
,”
Phys. Chem. Chem. Phys.
15
,
12480
12487
(
2013
).
22.
L.
Kattwinkel
and
O. M.
Magnussen
, “
Measurement of surface diffusion at the electrochemical interface by in situ linear optical diffraction
,”
ACS Meas. Sci. Au
(in press) (
2023
).
23.
X. D.
Zhu
, “
Optical diffractions as probes to surface diffusion of adsorbates
,”
Mod. Phys. Lett. B
06
,
1217
1235
(
1992
).
24.
J.
Ma
,
X.
Xiao
,
N. J.
DiNardo
, and
M. M. T.
Loy
, “
Diffusion of CO on Pt(111) studied by an optical diffraction method
,”
Phys. Rev. B
58
,
4977
4983
(
1998
).
25.
X.-D.
Xiao
,
Y.
Xie
, and
Y. R.
Shen
, “
Coverage dependence of anisotropic surface diffusion: CO/Ni(110)
,”
Phys. Rev. B
48
,
17452
17462
(
1993
).
26.
C. Z.
Zheng
,
C. K.
Yeung
,
M. M. T.
Loy
, and
X.
Xiao
, “
Step effects and coverage dependence of hydrogen atom diffusion on Pt(111) surfaces
,”
Phys. Rev. B
70
,
205402
(
2004
).
27.
C. Z.
Zheng
,
C. K.
Yeung
,
M. M. T.
Loy
, and
X.
Xiao
, “
Quantum diffusion of H on Pt(111): Step effects
,”
Phys. Rev. Lett.
97
,
166101
(
2006
).
28.
X. D.
Zhu
,
A.
Lee
,
A.
Wong
, and
U.
Linke
, “
Surface diffusion of hydrogen on Ni(100): An experimental observation of quantum tunneling diffusion
,”
Phys. Rev. Lett.
68
,
1862
1865
(
1992
).
29.
A.
Lee
,
X. D.
Zhu
,
L.
Deng
, and
U.
Linke
, “
Observation of a transition from over-barrier hopping to activated tunneling diffusion: H and D on Ni(100)
,”
Phys. Rev. B
46
,
15472
15476
(
1992
).
30.
G. X.
Cao
,
E.
Nabighian
, and
X. D.
Zhu
, “
Diffusion of hydrogen on Ni(111) over a wide range of temperature: Exploring quantum diffusion on metals
,”
Phys. Rev. Lett.
79
,
3696
3699
(
1997
).
31.
H. J.
Eichler
and
A.
Hermerschmidt
,
Photorefractive Materials and Their Applications 1: Basic Effects
(
Springer
,
New York
,
2006
), pp.
7
42
.
32.
V.
Climent
,
N.
Garcia-Araez
,
R. G.
Compton
, and
J. M.
Feliu
, “
Effect of deposited bismuth on the potential of maximum entropy of Pt(111) single-crystal electrodes
,”
J. Phys. Chem. B
110
,
21092
21100
(
2006
).
33.
Y.-E.
Sung
,
W.
Chrzanowski
,
A.
Wieckowski
,
A.
Zolfaghari
,
S.
Blais
, and
G.
Jerkiewicz
, “
Coverage evolution of sulfur on Pt(111) electrodes: From compressed overlayers to well-defined islands
,”
Electrochim. Acta
44
,
1019
1030
(
1998
).
34.
D.
Kolb
and
R. J.
Gale
, “
UV-visible reflectance spectroscopy
,” in
Spectroelectrochemistry Theory and Practice
(
Plenum Press
,
1988
).
35.
X.-D.
Xiao
, “
Surface diffusion studies by optical diffraction techniques
,” Ph.D. thesis,
University of California
,
1992
.
36.
L.
Kattwinkel
and
O. M.
Magnussen
, “
Optical reflectance studies on the oxidation of chemisorbed sulfur at the Pt(111) electrode
,”
Electrochim. Acta
434
,
141297
(
2022
).
37.
R. W.
Verhoef
and
M.
Asscher
, “
Diffusion on surfaces using laser diffraction: Effect of adsorbate lateral interactions
,”
Surf. Sci.
376
,
395
402
(
1997
).
38.
X.-D.
Xiao
,
X. D.
Zhu
,
W.
Daum
, and
Y. R.
Shen
, “
Optical second-harmonic diffraction study of anisotropic surface diffusion: CO on Ni(110)
,”
Phys. Rev. B
46
,
9732
9743
(
1992
).
39.
R.
Walder
,
N.
Nelson
, and
D. K.
Schwartz
, “
Single molecule observations of desorption-mediated diffusion at the solid-liquid interface
,”
Phys. Rev. Lett.
107
,
156102
(
2011
).
40.
M. J.
Skaug
,
J.
Mabry
, and
D. K.
Schwartz
, “
Intermittent molecular hopping at the solid-liquid interface
,”
Phys. Rev. Lett.
110
,
256101
(
2013
).
41.
H. A.
Yoon
,
N.
Materer
,
M.
Salmeron
,
M. A.
Van Hove
, and
G. A.
Somorjai
, “
Coverage-dependent structures of sulfur on Pt(111) studied by low-energy electron diffraction (LEED) and scanning tunneling microscopy (STM)
,”
Surf. Sci.
376
,
254
266
(
1997
).
42.
X. D.
Zhu
,
A.
Lee
, and
A.
Wong
, “
Detection of monolayer gratings of adsorbates by linear optical diffractions
,”
Appl. Phys. A
52
,
317
322
(
1991
).

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