Development of novel surface protection strategies for copper corrosion icyc 2015 19.07.15 2
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Transcript of Development of novel surface protection strategies for copper corrosion icyc 2015 19.07.15 2
Development of Novel Surface Development of Novel Surface Protection Strategies for Copper Protection Strategies for Copper
CorrosionCorrosion
5th INTERNATIONAL CONFERENCE FOR YOUNG CHEMISTS 2015, UNIVERSITY SAINS MALAYSIA, PENANG, AUGUST 05-07, 2015
Need for Surface ProtectionNeed for Surface Protection Surfaces of all materials are corrosion-prone due Surfaces of all materials are corrosion-prone due
to Climatic conditions & Chemical factorsto Climatic conditions & Chemical factors Destruction of materials leads to economy lossesDestruction of materials leads to economy losses Direct & Indirect losses due to corrosion amounts Direct & Indirect losses due to corrosion amounts
to $13 billions per yearto $13 billions per year
Need for Surface ProtectionNeed for Surface Protection……
Prime concern is Conservation of MaterialsPrime concern is Conservation of Materials World’s supply of materials is limited &World’s supply of materials is limited &
wastage / loss of materials leads to loss of wastage / loss of materials leads to loss of energy, cost escalation etc.,energy, cost escalation etc., Surface coating is an important strategy to Surface coating is an important strategy to
protect materials which are prone to decayprotect materials which are prone to decay
Copper – An Engineering MaterialCopper – An Engineering Material Copper has been commonly used in a wide range
of applications in heat conductors, heat exchangers because of its excellent thermal conductivity and mechanical workability.
Copper generally shows resistant against atmospheric corrosion and other forms of corrosion.
However, copper becomes very susceptible to corrosion in a significant rate in media that contain chloride ions.
Corrosion Protection MethodsCorrosion Protection Methods Prevention of corrosion in copper has attracted
many Researchers and many strategies have been developed to protect copper.
Among the available methods, electropolymerization techniques have become prominent nowadays due to its simplicity and wide range of applications.
Protection through ElectropolymerizationElectropolymerization- polymerization of an organic compounds (usually the heterocyclic compounds) under the influence of current.Electrodeposition of polymeric films at the surface of an electrode has opened up a new field at the convergence between two rich domains: electrochemistry of modified electrode and conjugated systems.
Simple process
It is enough to impose a sufficiently positive potential (Epolym) or to cycle
with a sufficiently high anodic limit (generally, it should exceed Epolym by
100–200 mV) on a metallic electrode.
By passing of an anodic current through the solution of monomer, film of
the corresponding polymer progressively grows at the electrode surface.
General Aspects of Electropolymerization
Solvent Electrolyte Bath composition and temperature pH Monomer concentration Hydrodynamic conditions (e.g., stirring or its
absence) Electrode surface area Pretreatment of its surface Shape of the working electrode Current density
Factors Affecting Electropolymerization
Electrodeposition can be done by any of the following methods
Cyclic VoltammetryCyclic Voltammetry
ChronoamperometryChronoamperometry
ChronopotentiometryChronopotentiometry
Work done in our lab...Electrosynthesis of poly-3-amino-1,2,4-triazole/TiO2 (3-ATA/TiO2) on copper
Electropolymerization Electropolymerization of ATAof ATA
Electropolymerization of ATA done using 0.2 M Electropolymerization of ATA done using 0.2 M
ATA with 0.1M ethanol/NaOH by CV-by scanning ATA with 0.1M ethanol/NaOH by CV-by scanning
the potential between -0.2 to 1.6 V vs SCE at a scan the potential between -0.2 to 1.6 V vs SCE at a scan
rate of 30 mV/s.rate of 30 mV/s.
CV of 3-ATA on Cu in MeOH-NaOH CV of monomer –free Cu in MeOH-NaOH
CV of 3-ATA with various concentrations of TiO2
Addition of TiO2 increases the peak current values suggesting the increase of rate of polymerization
Schematic representation of electropolymerization of 3-ATA
FT-IR Studies XRD pattern of (a) p-3-ATA (b) p-3-ATA/TiO2
For bare TiO2, the strong absorption at 686 cm-1 could be obtained due to Ti-O stretching . This band is weak in p-ATa+TiO2 composites due to the interaction of polymer with TiO2
XRD pattern of p-ATa showed a peak at 25o. This could be due to the polymer.
The 2Ө values at 37o, 47o and 55o showed the presence of Ti in the polymeric matrix and these values proved that the crystalline behavior of TiO2 particles was not affected during electropolymerization.
SEM image of p-3-ATA/TiO2
EDAX spectra of p-3-ATA/TiO2
Ti
SEM Suggests the incorporation of TiO2 particles in the polymeric matrix.
The average particle size of TiO2 is 0.67 µm.
The incorporation of TiO2 particles into the polymeric matrix was also confirmed by EDX analysis.
The intense peak at 0.40 and 4.5 KeV confirms the presence of Ti.
Nyquist plots Polarization plots
Materials Rct
(Ω cm-2 )
IE (%) icorr IE (%)
Bare 1043 --- 97.94 -0.1 M ATA 5051 95.3 18.4 81.20.1 M ATA + 10-3 M TiO2
11549 98.8 0.982 98.9
Thus, the study revealed that the incorporation of TiO2 at lower concentration decreases the porosity of the polymer and significantly increases the inhibition efficiency
Work done in our lab...
Electropolymerization of Electropolymerization of MMTAMMTA
Electropolymerization of MMTA done using 0.1 Electropolymerization of MMTA done using 0.1
M MMTA with 0.5M methanol/NaOH by CV-by M MMTA with 0.5M methanol/NaOH by CV-by
scanning the potential between 0 to 1.7 V vs SCE at a scanning the potential between 0 to 1.7 V vs SCE at a
scan rate of 10 mV/s.scan rate of 10 mV/s.N
N
N
SH
CH3
slow
NN
N
S
CH3
e
NN
N
S
CH3
NN
N
S
CH3
nH
fast ne
H
NN
N
S
CH3
NN
N
S
CH3n
(peak A)
(peak B)
FT-IR spectrum of (a) TiO2, (b) p-MMTA and (c) p-MMTA/TiO2
CV of p-MMTA over copper surface
As the number of cycles were increased, the anodic current values decreased. This suggested the formation of insulating polymeric films.
The strong absorption at 694 cm-1 is due to Ti–O stretching. This band appeared weak in the IR spectrum of the composite. This result strongly suggested the interaction of TiO2 with polymer.
CV of poly-MMTA on Cu FT-IR spectrum
The 2θ values at 35, 55, 60, 63 and 70 indicated the presence of TiO2 in the polymeric matrix. It also confirmed the crystalline nature of the incorporated TiO2.
XRD pattern of poly-MMTA/TiO2
Corrosion Inhibition Studies of poly-MMTA/TiO2
Materials Rct(Ω
cm-2 )
IE (%) icorr(µA cm-2)
IE (%)
Bare/Cu 1081 --- 70.12 ---p-MMTA/Cu 2450 55.4 33.12 52.7p- MMTA/TiO2/Cu 5201 79.1 15.62 77.7
Nyquist plots Polarization plots
The increase in Rct values and decrease in icorr values suggested the higher IE of p-MMTA/TiO2 composite on copper
M. G. Sethuraman et al. DOI: 10.1007/s11164-014-1876-2
Electrochemical synthesis of poly-3-amino-5-mercapto-1,2,4-triazole (AMTA) on copper and its protective effect in 3.5% NaCl medium (Res. Chem. Intermed.)
Electropolymerization Electropolymerization of AMTAof AMTA
Electropolymerization of AMTA done using 0.1 Electropolymerization of AMTA done using 0.1
M AMTA with 0.5M methanol/NaOH by CV-by M AMTA with 0.5M methanol/NaOH by CV-by
scanning the potential between -0.7 to 1.2 V vs SCE scanning the potential between -0.7 to 1.2 V vs SCE
at a scan rate of 10 mV/s.at a scan rate of 10 mV/s.
CV of AMTA
Schematic representation of electropolymerization of
AMTA on Cu
As the cycle increases, anodic peak current decreases, suggesting the formation of polymer film at the electrode surface
FT-IR spectra of (a) AMTA and (b) p-AMTA film
AMTA
Effect of scan rate on electropolymerization of AMTA
Materials IE (%)
Bare Cu --
p-AMTA/Cu 81
Corrosion Inhibition Studies of p-AMTA on Cu
Electrodes – Ecorr icorr βa βc IE
(mV/SCE) (µAcm−2) (mVdec−1) (mVdec−1) (%)
A 194.4 39.87 91 206 -- B 163.3 13.63 122 179 65.8 C 302.9 11.73 110 222 70.5 D 307.9 7.02 102 131 82.3 E 99.9 4.97 138 173 87.5 F 200.6 3.14 126 151 92.1
A – Bare Cu; B – poly-AMTA-Cu; C – poly-AMTA-La2O3-Cu; D – poly- AMTA-CeO2-Cu; E – poly-AMTA-TiO2-Cu; F – poly-AMTA-nano TiO2-Cu
Polarization Studies of p-AMTA and its composites
Protection through Superhydrophobic coatings
Self- Cleaning Mechanism (a) Normal Smooth Surface, (b) Superhydrophobic Surface
3131
Cont……Neinhuis, C.; Barthlott W. Ann. Bot. 1997, 79, 667–677
Superhydrophobic coatings fabrication can be done by any of the following
methods
Electroless depositionElectroless deposition
Immersion techniqueImmersion technique
Work done in our lab
Electroless DepositionDepending on its position in the electrochemical series, a metal higher in the series may be covered (plated) with the metal lower down in the series.
A well known example is the coverage of iron on copper in an acidified copper sulphate solution.
Two reactions, one anodic and the other cathodic, take place simultaneously at the surface. 3434
Cont……
Fabrication of ultra-water-repellent copper surface
3535
Experimental Copper electrodes
Immersed in 0.01 M AgNO3 for 60 s
Ag/Cu
Immersed in 0.1 M CA-SA for 6, 12 and
24 h
SA-CA/Cu
SA-CA/Ag/Cu
1st Route 2nd Route
Immersed in 0.1 M CA-SA for 6, 12 and 24 h
Seth
uram
an e
t al
., Su
rf.
Inte
rfac
e A
nal.
2015
, 47,
423
.
H3CCOOH
8
H2N SH60 o CEthanol
H3C8
O
HNSH
H2O
Stearic acid Cysteamine SA-CA organic molecular hybrid
C18 H36 O2 C2 H7 S N
3636
Results and Discussion
4000 3500 3000 2500 2000 1500Wavenumber (cm-1)
C-H (2922) anti-symmetric methylene
C-H (2847) symmetric methylene
S-H (2363) stretching
N-H (1591) bending
C=O(1637) stretching
C=O (1700) stretching
d-SA-CA/Ag/Cu
c-SA-CA/Cu
b-Pure CA
Tran
smitt
ance
(%)
a-Pure SA
FT-IR spectra of (a) pure SA, (b) pure CA,
(c) SA-CA/Cu and (d) SA-CA/Ag/Cu
EDX spectra of (a) SA-CA/Cu and (b) SA-CA/Ag/Cu
Spectral and Elemental Analyses
C, N, O, S and Cu
Ag, C, N, O, S and Cu
5 µm5 µm5 µm
5 µm 5 µm5 µm
5 µm
Surface Analyses
SEM and WCA images of (a) Ag/Cu ,SA-CA/Ag/Cu and SA/CA-Cu surfaces at
different immersion times: (b,e) 6 h, (c,f) 12 h and (d,g) 24 h (insert- a
photograph of sisal flower)
AFM images of (a) SA-CA /Cu
and (b) SA-CA/Ag/Cu surfaces
Specimen Immersion time (h)
Water contact angle (0)
Sliding angle (0)
SA-CA/Cu 6 150±2 7±112 154±1 6±224 169±2 3±1
SA-CA/Ag/Cu 6 168±2 3±112 176±1 1±224 178±1 1±2
Wettability of the as-prepared SA-CA/Cu and SA-CA/Ag/Cu surfaces at different immersion times
3939
-8 -7 -6 -5 -4 -3 -2 -1 0-0.4
-0.2
0.0
0.2
0.4
3
2 1
c
b
a
E (m
V)
log i (µ A cm-2)
a-Bare copperb-SA-CA/Cuc-SA-CA/Ag/Cu
-7 -6 -5 -4 -3 -2 -1 0-0.4
-0.2
0.0
0.2
0.4
c ba
a-Bare copperb-SA-CA/Cuc-SA-CA/Ag/Cu
E (m
V)log i (µ A cm-2)
Potentiodynamic polarization studies
Potentiodynamic polarization curves of (a) bare copper,
(b) SA-CA/Cu and (c) SA-CA/Ag/Cu surfaces after 1 h of immersion in 3.5 % NaCl
solution
Potentiodynamic polarization curves of (a) bare copper,
(b) SA-CA/Cu and (c) SA-CA/Ag/Cu surfaces after 168 h of immersion in 3.5 %
NaCl solution
(1) e Cu Cu -
(2) CuCl Cl Cu -
(3) CuCl Cl CuCl --2
Apparent Tafel
Transpassive region
Limiting region
Time (h) Specimen Ecorr (V) icorr (µA cm-2)1 Bare copper -219.93 5.185
SA-CA/Cu -120.61 2.586
SA-CA/Ag/Cu -56.10 1.258
168 Bare copper -216.23 6.824
SA-CA/Cu -169.30 3.021
SA-CA/Ag/Cu -118.58 1.847
Relevant electrochemical parameters of potentiodynamic polarization curves of bare
copper, SA-CA/Cu and SA-CA/Ag/Cu electrodes in 3.5 % NaCl
0 30 60 90 120 150 180165
170
175
180
185
Stat
ic c
onta
ct a
ngle
(o )
Time (days)
SA-CA/Ag/Cu
Variation in the static water contact angles of the as-prepared SA-CA/Ag/Cu surface as a function of
exposure time
Durability of the as-prepared SA-CA/Ag/Cu surface
4242
Work carryout in our lab
4343
Mussel-Glue threads like superhydrophobic coatings fabricated on aluminium surface
Kart
hik,
N.;
Seth
uram
an, M
. G. N
ew J
Chem
. 39
(201
5) 3
337
EXPERIMENTAL
2 Al + 3 Cu2+ 2 Al3+ + 3 Cu (1)
2 Al + 6 H+ 2 Al3+ + 3 H2 (3)
Cu2+ + 2 CH3 (CH2)11 NH2 [CH3 (CH2) 11 N]2 Cu + 2H+ (2)
4545
Results and DiscussionSpectral and Elemental Analyses
4000 3600 3200 2800 2400 2000 1600 1200 800 400
C-H (900) out-of-plane deformation
N-H (900-700) wag
C-N (1105-1035) stretching
N-H (1643) bend
scissoring
C-H (2874) symmetric methylene
C-H (2929) anti-symmetric
methylene
N-H (3500-3400) stretching
b
a
Tran
smitt
ance
(%)
Wavenumber (cm-1)
a-Pure LAb-LA/Cu/Al
FT-IR spectra of (a) pure LA and (b) LA/Cu/Al
EDX spectra of (a) Cu/Al and (b) LA/Cu/Al surfaces (assembled for 3 h)
O, Cu and Al
C, N, O, Cu and Al
4646
20 µm
50 µm50 µm
Surface Analyses
SEM and WCA of (a) Cu/Al, (b) LA/Cu/Al (assembled for 1 h) and (c) LA/Cu/Al (assembled for 3 h) surfaces. Arrow marks indicated the
formation of Mussel glue threads and circles indicated the presence of copper dendrites. Inset: a photograph of Mussel glue threads
Sethuraman et al. Journal of Taiwan Institute for Engineers (Under Review)
78°
135° 154°
4747
0 2 4 6 8 10 12 14135
140
145
150
155
160
165
170
175a
Stat
ic c
onta
ct a
ngle
(deg
ree)
pH
LA/Cu/Al
0 15 30 45
120
130
140
150
160
170
180b
Stat
ic c
onta
ct a
ngle
(deg
ree)
Time (d)
LA/Cu/Al
Durability and pH test of the as-prepared LA/Cu/Al surface
(a) Effect of pH and (b) exposure in air on the superhydrophicity of LA/Cu/Al surfaces
Applications
Self-cleaning cloths, glasses, board etc.
Anticorrosion coatings
Energy storage ( batteries and supercapacitors)
Semiconductors
Oil/water separation
Anti-fouling