Full Paper
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measured by using a paper Wilhelmy plate pressure sensor. Ultra-
pure Millipore Milli-Q water (resistivity 18.2 MWcm) was used as
the subphase. The spreading solutions, 2.5ꢄ10ꢀ5 m in [1H]Cl, were
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Sigma). To construct the Langmuir films, the solution was spread
using a Hamilton microsyringe held very close to an aqueous sur-
face, which allowed the surface pressure to return to a value as
close as possible to zero between each addition. The spreading
solvent was allowed to completely evaporate over a period of at
least 15 min before compression of the Langmuir film at a constant
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The films were deposited at a constant surface pressure by the ver-
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solid substrates used to support the LB films were quartz, glass,
and gold. Gold substrates were purchased from Arrandee, Schro-
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provide a precise energy calibration, the XPS binding energies
were referenced to the C 1s peak at 284.6 eV. The electrical proper-
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ICON) under humidity control (ca. 30%), with a N2 flow using Peak-
Force tunneling AFM (PF-TUNA) mode, and employing a PF-TUNA
cantilever from Bruker (coated with Pt/Ir 20 nm, ca. 25 nm radius,
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Acknowledgements
S.M., F.P.-M, and P.C. are grateful for financial assistance from
Ministerio de Economꢀa y Competitividad from Spain and fund-
ing from FEDER in the framework of projects CTQ2012-33198,
CSIC10-4E-805, and CSD2010-00024. S.M., F.P-M, and P.C. are
also grateful to the European SUDOE TRAIN2 project and the
Nanolito network through the MAT2011-13099-E project
funded by the Ministry of Economy of Spain for supporting
this collaborative work. R.J.N., P.J.L., and S.M-G. thank EPSRC
for funding, and P.J.L. also gratefully acknowledges support
from the Australian Research Council and the award of
a Future Fellowship (FT120100073). G.P. gratefully acknowledg-
es the award of a FPU fellowship from MEC and L.M.B acknowl-
edges her grant from Banco Santander.
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Keywords: electrochemistry · gold · Langmuir–Blodgett films ·
photochemistry · reduction
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