Metal–Organic Frameworks for Anti-Corrosion Applications
The corrosive medium used as reference in the electrochemical ex-
periments was the ASTM D 1384-87 solution (noted ASTM) with
the following composition: 148 mgL–1 Na2SO4, 138 mgL–1
NaHCO3 and 165 mgL–1 NaCl. The polarisation resistances (Rp)
were recorded over 5 h with measurements performed every 15 min
Experimental Section
Synthesis of Single and Binary Zinc Carboxylates as Powders: Crys-
tallised powders of zinc carboxylates have been synthesised in aque-
ous solution by the addition of sodium carboxylates to zinc nitrate
solution. During the addition, the solution was maintained at 65 °C
and pH = 5. Then the white precipitate was filtered, washed with
distilled water and finally dried in a desiccator. The solubility of
the different compounds was determined by Zn2+ analysis with
ICP-AES.
at a scan rate of 0.166 mVs–1 for a range of 20 mV (Ecorr
=
Ϯ10 mV). Test cycles in the climatic chamber (KBEA 300,
LIEBISCH) were carried out to simulate atmospheric corrosion:
8 h at 100% of humidity using twice-distilled water heated at 40 °C
followed by 16 h under ambient conditions.
Powder X-ray Diffraction Study: The X-ray diffraction patterns of
the mixtures were compared with those of the single zinc carboxyl-
ates, Zn(Cn)2 and Zn(CnЈ)2. The distances between the layers of
ZnO4 tetrahedrons were evaluated by SAXS (small-angle X-ray
scattering) using an INEL XRG 3000 diffractometer equipped with
a Cu anti-cathode. For structural resolution, X-ray powder diffrac-
tion data were collected at the European Synchrotron Radiation
Facility (ESRF) by using the synchrotron radiation of the very high
resolution powder diffractometer installed on the beam line
ID31.[12] A primary double-crystal monochromator Si(111) was
used for selecting the wavelength. Detection was ensured by a nine-
consecutive-crystals Ge(111) analyser. Each sample as a fine white
powder was introduced into a Lindeman tube (Φ = 1 mm). The
samples were spun on the axis of the diffractometer. Each capillary
was translated along the axis to give a fresh region of sample every
15 min to avoid radiation damage. Data were recorded by using a
wavelength of 0.851243(4) Å at 100 K with an interval of 0.003°
and a total counting time of 2 h. CCDC-791660 (ZnC10C14) and
-791661 (ZnC10C16) contain the supplementary crystallographic
data for this paper. These data can be obtained free of charge
from The Cambridge Crystallographic Data Centre via
www.ccdc.cam.ac.uk/data_request/cif.
Supporting Information (see footnote on the first page of this arti-
cle): Selected interatomic distances and fractional positions of
atoms in the structures of ZnC10C14 and ZnC10C16.
Acknowledgments
The authors would like to thank the ADEME AGRICE for fund-
ing this study and Arcelor, Total Lubrifiant for their support.
[1] a) C. Georges, E. Rocca, P. Steinmetz, Electrochim. Acta 2008,
53, 4839–4845; b) S. Jacques, E. Rocca, M. J. Stebe, J. Stein-
metz, Surface Coatings Technol. 2008, 202, 3878–3885; c) E.
Rocca, G. Bertrand, C. Rapin, J. C. Labrune, J. Electroanal.
Chem. 2001, 503, 133–140; d) J. Peultier, E. Rocca, J. Steinmetz,
Corros. Sci. 2003, 45, 1703–1716; e) E. Rocca, J. Steinmetz,
Corros. Sci. 2001, 43, 891–902.
[2] a) M. Edgar, R. Mitchell, A. M. Z. Slawin, P. Lightfoot, P. A.
Wright, Chem. Eur. J. 2001, 7, 5168–5175; b) Q.-R. Fang, G.-
S. Zhu, M. Xue, Q.-L. Zhang, J.-Y. Sun, X.-D. Guo, S.-L. Qiu,
S.-T. Xu, P. Wang, D.-J. Wang, Y. Wei, Chem. Eur. J. 2006, 12,
3754–3758; c) M. Eddaoudi, J. Kim, D. Vodak, A. Sudik, J.
Wachter, M. O’Keeffe, O. M. Yaghi, Proc. Natl. Acad. Sci.
USA 2002, 99, 4900–4904.
[3] E. Rocca, C. Caillet, A. Mesbah, M. Francois, J. Steinmetz,
Chem. Mater. 2006, 18, 6186–6193.
[4] E. Rocca, C. Rapin, F. Mirambet, Corros. Sci. 2004, 46, 653–
665.
[5] a) J. Peultier, M. François, J. Steinmetz, Acta Crystallogr., Sect.
C: Cryst. Struct. Commun. 1999, 55, 2064–2065; b) F. Lacout-
ure, J. Peultier, M. François, J. Steinmetz, Acta Crystallogr.,
Sect. C: Cryst. Struct. Commun. 2000, 56, 556–557; c) A. Mes-
bah, C. Juers, F. Lacouture, S. Mathieu, E. Rocca, M. François,
J. Steinmetz, Solid State Sci. 2007, 9, 322–328.
Coating Process and Characterisation: Coatings were performed on
square and double-faced zinc electrogalvanised steel sheets [pro-
vided by Arcelor Mittal (France)] by using a home-made pilot.[1]
The different steps of the coating process are as follows. The steel
sheets were degreased in an alkaline bath containing Gardoclean
S 5225 and Gardobond H 7352 (Chemetal) at 55 °C for 360 s. They
were then rinsed with deionised water at room temperature for 60 s
before carboxylating at 45 and 55 °C. After coating, the film mor-
phology was examined by using a Philips XL30 scanning electron
microscope equipped with a Kevex Sigma EDS in the secondary
electron and backscattered electron modes with an acceleration
voltage of 10 keV. On the zinc surface, the different phases [zinc,
zinc(II) carboxylate] were identified by energy-dispersive X-ray
(EDX) spectroscopy by measuring the C/Zn ratio and by imaging
the surface in the backscattered electron (BSE) mode. The surface
compounds were analysed by X-ray diffraction with an X’Pert Pro-
Philips diffractometer by using Cu-Kα1 and Cu-Kα2 wavelengths (λ1
= 1.54051 Å and λ2 = 1.54433 Å). The coating weight was deter-
mined by measuring the weight difference between the “carboxyl-
ated” sample and the same sample after coating dissolution under
ultrasound in 1,1-dichloroethane.
[6] A. Mesbah, C. Juers, M. François, E. Rocca, J. Steinmetz, Z.
Kristallog. Suppl. 2007, 26, 593.
[7] a) D. Feldman, M. M. Shapiro, D. Banu, C. J. Fuks, Sol. En-
ergy Mater. 1989, 18, 201–216; b) M. C. Costa, M. Sardo, M. P.
Rolemberg, J. A. P. Coutinho, A. J. A. Meirelles, P. Ribeiro-
Claro, M. A. Krähenbüh, Chem. Phys. Lipids 2009, 160, 85.
[8] M. A. Neumann, J. Appl. Crystallogr. 2003, 36, 356–365.
ˇ
[9] a) R. Cerný, V. Favre-Nicolin, Powder Diffr. 2005, 20, 359–365;
ˇ
b) R. Cerný, V. Favre-Nicolin, Z. Kristallogr. 2007, 222, 105–
113.
[10] T. Roisnel, J. Rodriguez-Carvajal, WinPLOTR: A windows tool
for powder diffraction pattern analysis, Materials Science Fo-
rum, 7th European Powder Diffraction Conference (EPDIC 7),
Barcelona, Spain, 2001, pp. 118–123.
[11] R. D. Shannon, Acta Crystallogr., Sect. A 1976, 32, 751–767.
[12] A. N. Fitch, J. Res. Natl. Inst. Stand. Technol. 2004, 109, 133–
142.
Electrochemical Measurements and Corrosion Tests: The electro-
chemical tests were performed under aerated conditions with a
three-electrode electrochemical cell connected to an EGG PAR
273A potentiostat driven by a computer. In this configuration, the
circular working electrode surface is vertical facing the Pt disk
counter-electrode. The reference electrode was a KCl saturated cal-
omel electrode (Hg/Hg2Cl2; E = +0.242 V/SHE), and all the work-
ing electrode potentials were measured relative to this reference.
Received: September 26, 2010
Published Online: January 21, 2011
Eur. J. Inorg. Chem. 2011, 1315–1321
© 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjic.org
1321