Densely packed open microspheres by soft template electropolymerization of benzotrithiophene-based monomers

Article abstract of DOI:10.1016/j.electacta.2020.137677

Here, a soft electropolymerization approach (called templateless) is used to prepare extremely ordered porous surface structures. For the first time, benzotrithiophene-based monomers are chosen for their high aromaticity and exceptional electropolymerizat

Full text of DOI:10.1016/j.electacta.2020.137677

Electrochimica Acta 369 (2021) 137677
Contents lists available at ScienceDirect
Electrochimica Acta
journal homepage: www.elsevier.com/locate/electacta
Densely packed open microspheres by soft template
electropolymerization of benzotrithiophene-based monomers
Yanis Levieux-Souida, Ananya Sathanikana, François Orangeb, Frédéric Guittarda,
Thierry Darmanina,∗
a Université Côte d’Azur, NICE Lab, 06200 Nice, France
b Université Côte d’Azur, Centre Commun de Microscopie Appliquée (CCMA), 06100 Nice, France
a r t i c l e i n f o
a b s t r a c t
Article history:
Here, a soft electropolymerization approach (called templateless) is used to prepare extremely ordered
porous surface structures. For the first time, benzotrithiophene-based monomers are chosen for their
high aromaticity and exceptional electropolymerization capacity. Different parameters are tested such
as the nature of the substituent, the presence of a ketone group between the monomer and the sub-
stituent, the water content and the electropolymerization method. Homogeneous structures are especially
obtained without ketone group, probably because the ketone group reduces π-stacking interactions be-
tween benzotrithiophene moieties. Unique results are obtained with the monomers with aromatic groups
(phenyl and naphthalene), which lead to densely packed huge open spheres by cyclic voltammetry and
in dichloromethane saturated with water. Here, just a phenyl group is sufficient compared to other works
with 3,4-phenylenedioxythiophene (PheDOT), 3,4-naphthalenedioxythiophene (NaphDOT) and thieno[3,4-
b]thiophene because BTT is already extremely aromatic. These porous surfaces could be used is the future
for a huge number of applications such as in water-harvesting systems, oil adsorbents, sensors or is drug
delivery.
Received 10 October 2020
Revised 22 December 2020
Accepted 22 December 2020
Available online 27 December 2020
Keywords:
Nanostructures
Template
Conducting polymer
Wettability
Hydrophobicity
© 2020 Elsevier Ltd. All rights reserved.
1. Introduction
the literature directly in water (H2O) and in the presence of surfac-
tant [14–20]. During electropolymerization, H2O can be oxidized or
Extremely controlled porous nanostructures have been explored
for a wide range of applications for example in catalyst, sensors,
adsorbents, drug delivery or for their wetting properties [1–7] In
Nature, the wetting properties are omnipresent (gecko toepads,
plant, wing surfaces,…) and is fundamental to well-adjust both
the surface energy and surface structures [8–11]. It was demon-
strated that vertically aligned nanotubes are an excellent choice for
their surface-area-to-volume ratio allowing to control the wetting
properties and their dimensions (diameter, height, porosity, shape)
[12,13].
reduced to produce O2 and H2 bubbles which are stabilized by the
surfactant and allowing the polymer growth around the gas bub-
bles.
However, most of the monomers are not soluble in H2O while
the electropolymerization in H2O often needs high monomer
concentration. It was recently reported that this soft template
electropolymerization is possible in organic solvent such as
dichloromethane (CH2Cl2) if H2O is present in solution in order
to form H2/O2 bubbles [21–26]. It is even possible without surfac-
tant if the monomer can stabilize the gas bubbles. Highly rigid and
aromatic thiophene-base molecules such as PheDOT, NaphDOT and
thienothiophene derivatives gave exceptional results such as verti-
cally aligned nanotubes, nanorings or coral-like structures.
In this work, we investigate for the first time extremely
aromatic and conjugated thiophene-base molecules called ben-
zotrithiophene (BTT), known for their exceptional electropoly-
merization capacity and optoelectronic properties [27–30]. Here,
BTT was chosen as monomer because it was demonstrated that
molecules favoring π-sticking interactions such as NaphDOT or
pyrene seem to be excellent choices [21,22,31]. The two series
studied are represented in Scheme 1. Both the influence of the
Their formation on substrates often needs complex and long
processes, typically using hard templates [14,15]. The template-
less electropolymerization is an excellent candidate to prepare or-
dered surface structures very quickly, but also with tunable shape
(nanotubes, nanocaps…) [14–26]. In this process, gas bubbles are
formed on the substrate during electropolymerization and are used
as soft template. For example, pyrrole was extensively studied in
∗
Corresponding author.
E-mail address: thierry.darmanin@unice.fr (T. Darmanin).
https://doi.org/10.1016/j.electacta.2020.137677
0013-4686/© 2020 Elsevier Ltd. All rights reserved.

Y. Levieux-Souid, A. Sathanikan, F. Orange et al.
Electrochimica Acta 369 (2021) 137677
For the first reaction, to an ice-cooled solution of 2,3-
dibromothiophene (10.0 g, 0.0413 mol) and the corresponding
acid chloride (1,2 eq., 0.049 mol) in anhydrous dichloromethane
(200 mL) was added aluminum chloride (8.26 g, 0.062 mol)
portion-wise during 15 min. The reaction mixture was stirred for
24 h and then quenched with ice-cold hydrochloric acid (1 M,
50 mL) and water (50 mL). The quenched reaction mixture was ex-
tracted with chloroform and dried over anhydrous sodium sulphate
and concentrated to afford the crude product. Purification by col-
umn chromatography (silica gel, 80/20: cyclohexane/chloroform).
2,3-Dibromo-5-acetylthiophene: Yield 50%; oily Yellow-Orange
solid; 1H NMR (200 MHz, CDCl3) δ 7.47 (s, 1H), 2.51 (s, 3H).
2,3-Dibromo-5-butyrylthiophene: Yield 48%; oily Yellow-
Orange solid; 1H NMR (300 MHz, CDCl3) δ 7.47 (s, 1H), 2.80 (t,
J = 7.2 Hz, 2H), 1.70 (m, 2H), 0.92 (t, J = 7.4 Hz, 3H).
2,3-Dibromo-5-hexanoylthiophene: Yield 86%; oily Yellow-
Orange solid; 1H NMR (200 MHz, CDCl3) δ 7.46 (s, 1H), 2.79 (t,
J = 7.2 Hz, 2H), 1.71 (m, 2H), 1.34 (m, 2H), 0.89 (t, J = 6.7 Hz, 3H).
2,3-Dibromo-5-octanoylthiophene: Yield 40%; oily Yellow-
Orange solid; 1H NMR (300 MHz, CDCl3) δ 7.49 (s, 1H), 2.82 (t,
J = 7.2 Hz, 2H), 1.73 (m, 2H), 1.32 (m, 6H), 0.89 (t, J = 6.7 Hz, 3H).
2,3-Dibromo-5-decanoylthiophene: Yield 70%; oily Yellow-
Orange solid 1H NMR (300 MHz, CDCl3) δ 7.49 (s, 1H), 2.82 (t,
J = 7.2 Hz, 2H), 1.73 (m, 2H), 1.30 (m, 10H), 0.87 (t, J = 6.7 Hz,
3H).
Scheme 1. Benzotrithiophene based monomers investigated in the manuscript.
2,3-Dibromo-5-benzoylthiophene: Yield 83%; oily Yellow-
Orange solid; 1H NMR (300 MHz, CDCl3) δ 7.82 (m, 2H), 7.57 (m,
3H), 7.42 (s, 1H).
substituent (various linear alkyl chains and aromatic groups) as
well as the presence of a ketone group between the monomer
and the substituent on the resulting surface structures and hy-
drophobicity are studied. Because it was reported that the pres-
ence of H2O has a huge influence on the formation of porous struc-
tures and especially on their number [25], two solvents are studied
CH2Cl2 and CH2Cl2 saturated with H2O called here CH2Cl2 + H2O.
2,3-Dibromo-5-naphtanoylthiophene: Yield 58%; oily Yellow-
Orange solid;1H NMR (300 MHz, CDCl3) δ 8.38 (s, 1H), 7.97 (m,
4H), 7.58 (m, 3H).
For the second step, a suspension of 1 (1 eq), thiophene-3-
boronic acid (2.2 eq) and sodium carbonate (4,24 g) was prepared
in toluene (60 mL), ethanol (10 mL) and water (20 mL). Then,
tetrakis(triphenylphosphine)palladium(0) (0.069 eq) was added
and the reaction mixture was heated at 100 °C to reflux for
24 h. The solvents were evaporated. After purification by col-
umn chromatography (silica gel, 50/50: cyclohexane/chloroform),
the crude product obtained was mainly an intermediate product.
A suspension of this intermediate product (1 eq), thiophene-3-
boronic acid (2.2 eq) and sodium carbonate (4,24 g) in toluene
2. Materials and method
2.1. Monomer synthesis
The synthesis way is schematized in Scheme 2. Monomers were
synthesized in four steps from 2,3-dibromothiophene, adjusting a
procedure reported in the literature.27 1H and 13C NMR spectra are
available in Supporting Information.
Scheme 2. Chemical route to the monomers.
2

Y. Levieux-Souid, A. Sathanikan, F. Orange et al.
Electrochimica Acta 369 (2021) 137677
Fig. 1. Electropolymerization of BTT-CO-C3 and BTT-C4 (10 mM) by cyclic voltammetry (5 scans) in 0.1 M Bu4NClO4 / CH2Cl2 (left) and CH2Cl2 + H2O (right) at a scan rate
of 20 mV s–1
.
(20 mL), ethanol (20 mL) and water (20 mL) was performed
again. Then tetrakis(triphenylphosphine)palladium(0) (0.069 eq)
was added and the reaction mixture was heated at 100 °C to reflux
for 24 h. Then, the solvents were evaporated. Purification by col-
umn chromatography (silica gel, 50/50: cyclohexane /chloroform).
5-Acetyl-2,3-bis(3-thienyl)thiophene: Yield 18%; pale yellow
solid 1H NMR (300 MHz, CDCl3) δ 7.69 (s, 1H), 7.29 (m, 3H), 7.26
(dd, J = 3.0 Hz, J = 1.3 Hz, 1H), 7.00 (m, 2H), 2.59 (s, 3H).
5-Butyryl-2,3-bis(3-thienyl)thiophene: Yield 21%; pale yellow
solid 1H NMR (300 MHz, CDCl3) δ 7.70 (s, 1H), 7.28 (m, 3H), 7.24
(dd, J = 3.0 Hz, J = 1.3 Hz, 1H), 7.01 (m, 2H), 2.89 (t, J = 7.3 Hz,
2H), 1.80 (m, 2H), 1.00 (t, J = 7.4 Hz, 3H).
For the third step, to an ice-cooled solution of 2 (1 eq) in an-
hydrous dichloromethane (140 mL) was added boron trifluoride
diethyl etherate (1.3 eq) after which 2,3-dichloro-5,6-dicyano-1,4-
benzoquinone (1.2 eq) was added portion wise for 10 min. The
reaction mixture was allowed to warm to room temperature for
48 h and was subsequently quenched by addition of zinc (7.7 eq)
and methanol (70 mL). After stirring overnight, the reaction mix-
ture was filtered, washed with chloroform, dried over anhydrous
sodium sulphate and concentrated to afford the crude product. Pu-
rification by column chromatography (silica gel, 50/50: cyclohex-
ane/chloroform).
BTT-CO-C1: Yield 16%; White solid; m.p. 162.5 °C; 1H NMR
(300 MHz, CDCl3) δ 8.13 (s, 1H), 7.60 (d, J = 5.4 Hz, 1H), 7.48
(d, J = 5.4 Hz, 1H), 7.43 (d, J = 5.4 Hz, 1H), 7.40 (d, J = 5.4 Hz,
1H), 2.62 (s, 3H); 3C NMR (75 MHz, CDCl3) δ 191.76, 142.09, 136.47,
133.22, 132.19, 131.09, 127.96, 125.54, 125.37, 122.64, 122.43, 26.89.
BTT-CO-C3: Yield 82%; White solid; m.p. 155.0 °C; 1H NMR
(300 MHz, CDCl3) δ 8.32 (s, 1H), 7.76 (d, J = 5.4 Hz, 1H), 7.63
(d, J = 5.4 Hz, 1H), 7.55 (d, J = 5.4 Hz, 1H), 7.53 (d, J = 5.4 Hz,
1H), 3.06 (t, J = 7.2 Hz, 2H), 1.89 (m, 2H), 1.08 (t, J = 7.4 Hz, 3H);
13C NMR (75 MHz, CDCl3) δ 194.35, 142.13, 136.22, 133.56, 133.26,
132.25, 131.68, 131.17, 127.13, 125.50, 125.32, 122.66, 122.48, 41.25,
18.28, 13.93.
BTT-CO-C5: Yield 23%; White solid; m.p. 78.2 °C; 1H NMR
(300 MHz, CDCl3) δ 8.30 (s, 1H), 7.72 (d, J = 5.4 Hz, 1H), 7.62 (d,
J = 5.4 Hz, 1H), 7.54 (d, J = 5.4 Hz, 1H), 7.52 (d, J = 5.4 Hz, 1H),
3.06 (t, J = 7.2 Hz, 1H), 1.88 (m, 2H), 1.41 (t, J = 6.4 Hz, 5H), 0,93
(m,3H); 13C NMR (75 MHz, CDCl3) 194.50, 142.09, 136.20, 133.26,
132.24, 131.15, 127.11, 125.51, 125.32, 122.68, 122.51, 39.38, 31.57,
24.54, 22.55, 13.99.
BTT-CO-C7: Yield 47%; White solid; m.p. 81.1 °C; 1H NMR
(300 MHz, CDCl3 δ 8.03 (s, 1H), 7.52 (d, J = 5.4 Hz, 1H), 7.41 (m,
3H), 2.97 (t, J = 7.4 Hz, 2H), 1.80 (m, 2H), 1.34 (m, 8H), 0,90 (t,
J = 6.0 Hz, 3H); 13C NMR (75 MHz, CDCl3) 194.20, 141.78, 135.78,
5-Hexanoyl-2,3-bis(3-thienyl)thiophene: Yield 44%; pale yel-
low solid 1H NMR (300 MHz, CDCl3) δ 7.70 (s, 1H), 7.28 (m,
3H), 7.25 (dd, J = 3.0 Hz, J = 1.3 Hz, 1H), 7.00 (m, 2H), 2.89 (t,
J = 7.4 Hz, 2H), 1.78 (m, 2H), 1.39 (m, 4H), 0.93 (t, J = 7.0 Hz, 3H).
5-Octanoyl-2,3-bis(3-thienyl)thiophene: Yield 27%; pale yel-
low solid 1H NMR (300 MHz, CDCl3) δ 7.68 (s, 1H), 7.28 (m,
3H), 7.21 (dd, J = 3.0 Hz, J = 1.3 Hz, 1H), 7.00 (m, 2H), 2.88 (t,
J = 7.4 Hz, 2H), 1.76 (m, 2H), 1.32 (m, 6H), 0.88 (t, J = 6.7 Hz, 3H).
5-Decanoyl-2,3-bis(3-thienyl)thiophene: Yield 29%; pale yel-
low solid 1H NMR (300 MHz, CDCl3) δ 7.67 (s, 1H), 7.30 (m,
3H), 7.21 (dd, J = 3.0 Hz, J = 1.3 Hz, 1H), 7.00 (m, 2H), 2.92 (t,
J = 7.4 Hz, 2H), 2.86 (m, 2H), 1.25 (m, 8H), 0.87 (t, J = 6.7 Hz, 3H).
5-Benzoyl-2,3-bis(3-thienyl)thiophene: Yield 49%; pale yellow
solid 1H NMR (300 MHz, CDCl3) δ 7.93 (m, 2H), 7.67 (s, 1H), 7.55
(m, 3H), 7.35 (m, 3H), 7.25 (dd, J = 3.0 Hz, J = 1.4 Hz, 1H), 7.07
(dd, J = 4.9 Hz, J = 1.4 Hz, 1H), 7.02 (dd, J = 4.9 Hz, J = 1.4 Hz,
1H).
5-Naphtanoyl-2,3-bis(3-thienyl)thiophene: Yield 43%; pale
yellow solid 1H NMR (300 MHz, CDCl3) 8.47 (s, 1H), 8.00 (m, 4H),
7.74 (s, 1H), 7.63 (m, 3H), 7.38 (m, 3H), 7.26 (dd, J = 2.9 Hz,
J = 1.2 Hz, 1H),7.09 (dd, J = 4.9 Hz, J = 1.2 Hz, 1H), 7.04 (dd,
J = 4.9 Hz, J = 1.4 Hz, 1H).
3

Y. Levieux-Souid, A. Sathanikan, F. Orange et al.
Electrochimica Acta 369 (2021) 137677
Fig. 2. Cyclic voltammogram of electrodeposited surfaces obtained from BTT-CO-C3 and BTT-C4 in 0.1 M Bu4NClO4 / CH2Cl2 at a scan rate of 20 mV s–1
.
Table 1
133.15, 132.91, 131.84, 131.26, 130.79, 126.72, 125.17, 124.93, 122.38,
Monomer and polymer oxidation potential.
122.31, 39.29, 31.79, 31.73, 29.43, 29.36, 29.24, 29.15, 24.74, 22.72,
14.19.
BTT-CO-C9: Yield 25%; White solid; m.p. 78.5 °C; 1H NMR
Monomer
Eox
[V vs SCE]
Eox
[V vs SCE]
polymer
monomer
BTT-CO-C1
BTT-CO-C3
BTT-CO-C5
BTT-CO-C7
BTT-CO-C9
BTT-CO-Ph
BTT-CO-NaPh
BTT-C2
2.27
1.96
1.96
2.05
2.10
2.27
2.33
2.12
2.10
2.10
2.00
1.95
2.20
2.36
1.90
1.96
1.89
1.92
1.91
1.91
1.91
1.99
1.95
1.99
1.98
1.95
1.95
2.00
(300 MHz, CDCl3) δ 8.12 (s, 1H), 7.60 (d, J = 5.4 Hz, 1H), 7.49
(m, 3H), 3.03 (t, J = 7.4 Hz, 2H), 1.84 (m, 2H), 1.31 (t, 12H),
0,93 (t, J = 6.7 Hz, 3H); 13C NMR(75 MHz, CDCl3) 194.35, 141.95,
136.00, 133.36, 133.10, 132.05, 131.47, 130.99, 126.90, 125.33,
125.11, 122.53, 122.41, 39.37, 31.92, 29.54, 29.45, 29.34, 26.94, 24.81,
22.71, 14.16.
BTT-CO-Ph: Yield 45%; White solid; m.p. 171.4 °C; 1H NMR
(300 MHz, CDCl3) δ 8.19 (s, 1H), 7.96 (m, 2H), 7.62 (m, 5H), 7.50 (d,
J = 5.4 Hz, 1H), 7.48 (d, J = 5.4 Hz, 1H); 13C NMR (75 MHz, CDCl3)
189.14, 141.28, 138.13, 136.71, 133.72, 133.28, 132.44, 132.18, 131.72,
131.02, 130.47, 129.30, 128.62, 125.56, 125.32, 122.70, 122.57.
BTT-CO-NaPh: Yield 40%; White solid; No m.p.; 1H NMR
(300 MHz, CDCl3) δ 8.52 (s, 1H), 8.31 (s, 1H), 8.00 (m, 4H), 7.72
(d, J = 5.4 Hz, 1H), 7.70 (d, J = 5.4 Hz, 1H), 7.62 (m, 2H), 7.56
(d, J = 5.4 Hz, 1H), 7.54 (d, J = 5.4 Hz, 1H); 13C NMR (75 MHz,
CDCl3) 189.13, 141.44, 136.74, 135.41, 135.23, 133.76, 133.45, 133.40,
133.33, 133.17, 132.38, 132.24, 131.08, 130.53, 129.38, 128.60,
128.31, 127.90, 127.83, 127.02, 126.97, 125.60, 125.35, 122.74,
122.61.
BTT-C4
BTT-C6
BTT-C8
BTT-C10
BTT-C1-Ph
BTT-C1-NaPh
1.82 (m, 2H) 1.36 (m, 4H), 0.94 (t, J = 7.2 Hz, 3H). 13C NMR
(75 MHz, CDCl3) 145.36, 132.84, 132.31, 131.49, 129.76, 124.75,
124.03, 122.74, 122.27, 119.37, 31.62, 31.50, 30.91, 30.76, 28.82,
22.59, 14.10.
BTT-C8: Yield 43%; White solid; m.p. 45.2 °C; δ 7.68 (d, 5.4 Hz,
1H), 7.54 (d, J = 5.4 Hz, 1H), 7.47 (d, J = 5.4 Hz, 1H), 7.45 (d,
J = 5.4 Hz, 1H), 7.41 (t, J = 0.9 Hz, 1H), 2.95 (t, J = 7.3 Hz, 2H),
1.90 (m, 2H), 1.20 (m, 10H), 0.85 (t, J = 6.6 Hz, 3H); 13C NMR
(75 MHz, CDCl3) 145.39, 132.87, 132.38, 131.52, 124.78, 124.05,
122.78, 122.32, 119.39, 77.69, 77.05, 76.42, 31.91, 31.58, 30.80, 29.42,
29.27, 29.19, 22.71, 14.15.
BTT-C10: Yield 40%; Liquid; 1H NMR (200 MHz, CDCl3); δ 7.69
(d, 5.4 Hz, 1H), 7.55 (d, J = 5.4 Hz, 1H), 7.48 (d, J = 5.4 Hz,
1H), 7.46 (d, J = 5.4 Hz, 1H), 7.42 (t, J = 0.9 Hz, 1H), 3.00 (t,
J = 7.4 Hz, 2H), 1.90 (m, 2H), 1.30 (m, 16H), 0.85 (t, J = 6.2 Hz, 3H);
13C NMR (75 MHz, CDCl3) 145.41, 124.79, 124.06, 122.78, 122.32,
119.40, 77.66, 77.03, 76.39, 31.92, 31.56, 30.79, 29.62, 29.58, 29.42,
29.35, 29.15, 22.70, 14.13.
BTT-C1-Ph: Yield 41%; White solid; m.p. 120.8 °C; 1H NMR
(200 MHz, CDCl3) δ 7.65 (d, J = 5.4 Hz, 1H), 7.50 (d, J = 5.4 Hz, 1H),
7.46 (m, 3H), 7.37 (m, 4H), 4.33 (s, 2H); 13C NMR (75 MHz, CDCl3)
131.44, 128.76, 128.71, 126.79, 124.89, 124.20, 122.78, 122.30,
120.64, 102.96, 77.65, 77.33, 77.21, 77.18, 77.02, 76.84, 76.79, 76.62,
76.38, 36.94.
BTT-C1-NaPh: Yield 67%; White solid; m.p. 150.4 °C; 1H NMR
(300 MHz, CDCl3) δ 7.86 (m, 4H), 7.65 (d, J = 5.4 Hz, 1H), 7.48 (m,
7H), 4.50 (s, 2H); 13C NMR (75 MHz, CDCl3) 143.73, 137.26, 133.61,
132.76, 132.45, 132.42, 131.85, 131.44, 130.93, 130.10, 128.35,
127.71, 127.20, 127.10, 126.21, 125.72, 124.90, 124.21, 122.79, 122.30,
120.84, 37.11.
For the fourth step, to a suspension of 3 (1 eq) in ethylene gly-
col (10 mL) was added hydrazine monohydrate (50 eq) and potas-
sium hydroxide (30 eq) and the reaction mixture was stirred at
190 °C overnight. The cooled reaction mixture was poured into
water, extracted with chloroform, dried over sodium sulphate and
concentrated to afford the crude product. Purification was per-
formed by column chromatography (silica gel, 50/50: cyclohex-
ane/chloroform).
BTT-C2: Yield 74%; White solid; m.p. 103.2 °C; 1H NMR
(300 MHz, CDCl3) δ 7.69 (d, 5.4 Hz, 1H), 7.56 (d, J = 5.4 Hz,
1H), 7.48 (d, J = 5.4 Hz, 1H), 7.46 (d, J = 5.4 Hz, 1H), 7.43 (t,
J = 1.1 Hz, 1H), 3.07 (m, 2H), 1.44 (t, J = 7.2 Hz, 3H); 13C NMR
(75 MHz, CDCl3) δ 146.84, 132.88, 132.41, 131.52, 130.95, 130.82,
129.82, 124.79, 124.08, 122.76, 122.32, 118.69, 24.12, 15,83.
BTT-C4: Yield 40%; White solid; m.p. 43.8 °C; 1H NMR
(300 MHz, CDCl3 δ 7.69 (d, 5.4 Hz, 1H), 7.55 (d, J = 5.4 Hz, 1H),
7.48 (d, J = 5.4 Hz, 1H), 7.46 (d, J = 5.4 Hz, 1H), 7.42 (t, J = 1.0 Hz,
1H), 3.01 (t, J = 7.5 Hz, 2H), 1.81 (m, 2H), 1.50 (m, 2H), 0.99 (t,
J = 7.3 Hz, 3H). 13C NMR (75 MHz, CDCl3) δ 145.30, 132.83, 132.34,
131.48, 131.01, 130.78, 129.76, 124.77, 124.05, 122.75, 122.29, 119.37,
33.61, 30.43, 22.20, 13.84.
BTT-C6: Yield 51%; White solid; m.p. 42.8 °C; 1H NMR
(300 MHz, CDCl3 δ 7.69 (d, 5.4 Hz, 1H), 7.56 (d, J = 5.4 Hz,
1H), 7.48 (d, J = 5.4 Hz, 1H), 7.46 (d, J = 5.4 Hz, 1H), 7.42
(t,
J
=
0.9 Hz, 1H), 3.01 (t,
J
=
7.5 Hz, 2H), 2.03 (m, 2H),
4

Y. Levieux-Souid, A. Sathanikan, F. Orange et al.
Electrochimica Acta 369 (2021) 137677
Table 2
Arithmetic (Ra) and quadratic (Rq) surfaces roughness, surface area (for an analysed surface of 0.275 mm2) and
roughness parameter (r) of Wenzel equation, for the surfaces obtained by cyclic voltammetry in CH2Cl2 + H2O.
Monomer
BTT-CO-C1
Number of deposition scans
Ra [μm]
Rq [μm]
Surface area [mm2]
r
1
3
5
1
3
5
1
3
5
1
3
5
1
3
5
1
3
5
1
3
5
1
3
5
1
3
5
1
3
5
1
3
5
1
3
5
1
3
5
1.6
0.3
2.6
0.4
0.872
∗
∗
3.2
∗
∗
∗
∗
∗
∗
BTT-CO-C3
BTT-CO-C5
BTT-CO-C7
BTT-CO-Ph
BTT-CO-NaPh
BTT-C2
0.15
0.63
0.70
0.07
0.13
0.87
0.07
0.56
1.6
0.04
0.05
0.13
0.02
0.02
0.08
0.02
0.07
0.42
1.0
0.10
0.291
0.361
0.433
0.275
0.275
0.702
0.275
0.390
0.480
0.600
1.1
1.3
1.6
1.0
1.0
2.6
1.0
1.4
1.7
2.2
0.13
0.16
1.0
0.08
0.20
1.0
0.03
0.04
0.17
0.15
0.84
2.2
0.2
0.12
0.2
0.25
2.1
0.3
0.7
4.2
0.4
0.9
4.2
5.5
0.840
∗
3.1
∗
∗
∗
0.90
0.01
1.2
0.2
0.510
∗
∗
1.9
∗
∗
∗
∗
∗
∗
0.92
1.5
0.25
0.2
0.2
0.04
1.2
0.3
0.529
0.812
0.925
0.780
0.947
0.763
0.275
0.280
0.581
0.277
0.750
0.801
0.281
0.600
0.606
1.9
2.9
3.4
2.8
3.4
2.8
1.0
1.0
2.1
1.0
2.7
2.9
1.0
2.2
2.2
2.0
0.2
1.8
2.3
0.3
BTT-C4
0.84
1.8
1.3
0.1
0.3
0.2
2.4
0.40
0.35
1.8
2.4
BTT-C6
0.08
0.23
1.46
0.14
1.6
0.01
0.12
0.30
2.0
0.02
0.05
0.30
0.04
0.16
0.02
BTT-C8
230
2.0
35
0.2
0.20
1.45
0.22
1.2
023
1.90
0.32
1.8
0.25
0.07
0.28
BTT-C10
0.05
0.2
0.22
0.10
1.5
2.0
0.30
0.11
BTT-C1-Ph
BTT-C1-NaPh
0.78
1.1
0.495
∗
∗
1.8
∗
∗
∗
∗
∗
∗
0.30
0.09
0.45
0.11
0.283
∗
∗
1.0
∗
∗
∗
∗
∗
∗
∗too rough for the optical profilometry.
Fig. 3. SEM images obtained with BTT-CO-C3 and BTT-C4 in CH2Cl2. 3 scans at a scan rate of 20 mV s−1
.
2.2. Soft template electropolymerization
trode (SCE) as the reference electrode. Tetrabutylammonium per-
chlorate (Bu4NClO4) was used as the supporting electrolyte with
a concentration of 0.1 M. Two solvents were tested CH2Cl2 and
CH2Cl2 + H2O. CH2Cl2 + H2O was prepared by mixing CH2Cl2 with
a high amount of H2O and discarding the aqueous phase. The de-
positions were performed either by cyclic voltammetry (1, 3 and 5
The soft electropolymerization experiments were realized with
a potentiostat (Autolab from Metrohm) via three electrodes: 2
cm2 gold-silicon wafer as the working electrode, a glassy car-
bon rod as the counter-electrode and a saturated calomel elec-
5

Y. Levieux-Souid, A. Sathanikan, F. Orange et al.
Electrochimica Acta 369 (2021) 137677
Fig. 4. SEM images obtained with BTT-CO-C1, BTT-CO-C3, BTT-CO-C5 and BTT-CO-C7 in CH2Cl2 + H2O. 3 scans at a scan rate of 20 mV s−1. The substrates are not inclined
(on the left) and inclined at 45° (on the right).
6

Y. Levieux-Souid, A. Sathanikan, F. Orange et al.
Electrochimica Acta 369 (2021) 137677
Fig. 5. SEM images obtained with BTT-CO-Ph and BTT-CO-NaPh in CH2Cl2 + H2O. 3 scans at a scan rate of 20 mV s−1. The substrates are not inclined (on the left) and
inclined at 45° (on the right).
scans at a scan rate of 20 mV s−1) or at constant potential (12.5,
Table 3
Wettability data for the polymer
25, 50, 100, 200 and 400 mC cm−2 at a potential of the monomer
films obtained by cyclic voltam-
oxidation potential Eox).
metry (3 scans in CH2Cl2 + H2O at
the san rate of 20 mV s−1
.
Smooth surfaces were also prepared in CH2Cl2 at constant po-
tential and using an ultra-short deposition charge of 1 mC cm−2
.
Monomer
θw [deg]
Then, the polymers were reduced by cyclic voltammetry: 1 back
scan from Eox to −1 V.
BTT-CO-C1
BTT-CO-C3
BTT-CO-C5
BTT-CO-C7
BTT-CO-C9
BTT-CO-Ph
BTT-CO-NaPh
BTT-C2
34.0
67.5
97.8
72.1
74.8
66.2
109.4
91.6
52.7
90.6
65.0
72.7
76.1
94.8
11.3
2.1
3.7
3.1
2.9
4.4
2.3. Surface characterization
16.6
After metallization, surfaces structures were imaged via scan-
10.3
0.3
ning electron microscopy (SEM) (6700F microscope from JEOL)
BTT-C4
BTT-C6
3.2
without and with
a substrate inclination of 45°. The surface
BTT-C8
11.0
3.9
hydrophobicity was characterized via goniometer (DSA30 from
Bruker) with 2 μL water droplets and by measuring the apparent
contact angles with water (θw) taken at the triple point (n = 5).
IR spectra were performed on a Spectrum 100 FT-IR spectrometer
(Perkin Elmer, USA) with a diamond attenuated total reflectance
(ATR) top plate accessory. A Tescan Vega 3 XMU scanning electron
microscope equipped with an X-MaxN 50 EDX detector was used
for the EDX analyses. The arithmetic (Ra) and quadratic (Rq) rough-
ness were obtained with a WYKO NT1100 optical profiling system
from Bruker using the objective 20X, and the field of view 0.5X
(analysed surface of 0.275 mm2). The white light vertical scanning
Interferometry (VSI) was used for the surfaces with low roughness
and the red light High Mag Phase Shift Interferometry (PSI) was
used for the surfaces with high roughness.
BTT-C10
BTT-C1-Ph
BTT-C1-NaPh
6.5
16.5
3. Results and discussion
In this work, in agreement to previous works [25], two solvents
were tested for soft template electropolymerization: CH2Cl2 and
CH2Cl2 saturated with H2O (CH2Cl2 + H2O). As reported in liter-
ature, the formation of H2 bubbles from H2O (2 H2O + 2 e– → H2
(bubbles) + 2 OH−) is perfectly visible by cyclic voltammetry at ≈
−0.5 V vs SCE during the back scan, but only for CH2Cl2 + H2O.
7

Y. Levieux-Souid, A. Sathanikan, F. Orange et al.
Electrochimica Acta 369 (2021) 137677
Fig. 6. SEM images obtained with BTT-C2, BTT-C4, BTT-C6 and BTT-C8 in CH2Cl2 + H2O. 3 scans at a scan rate of 20 mV s−1. The substrates are not inclined (on the left) and
inclined at 45° (on the right).
8

Y. Levieux-Souid, A. Sathanikan, F. Orange et al.
Electrochimica Acta 369 (2021) 137677
Fig. 7. SEM images obtained with BTT-C1-Ph and BTT-C1-NaPh in CH2Cl2 + H2O. 3 scans at a scan rate of 20 mV s−1. The substrates are not inclined (on the left) and
inclined at 45° (on the right).
Table 4
Young’s angles and surface energy for the smooth polymer films.
Monomer
θY,w [deg]
θY,diiodo [deg]
θY,hexad [deg]
γ S,P
γ S,D
γ S
BTT-CO-C1
BTT-CO-C3
BTT-CO-C5
BTT-CO-C7
BTT-CO-C9
BTT-CO-Ph
BTT-CO-NaPh
BTT-C2
61.0
63.9
61.8
66.7
66.2
61.2
59.4
60.1
66.4
68.4
70.5
65.4
61.6
64.3
1.0
1.1
2.6
2.1
2.4
3.5
5.8
1.7
2.6
4.4
3.3
6.8
1.0
3.9
36.0
31.2
26.9
28.4
28.8
21.6
33.4
24.0
33.6
26.5
22.3
27.1
27.0
24.8
4.3
3.1
5.8
3.9
1.9
2.4
2.7
5.0
5.5
2.1
4.6
1.4
4.1
1.7
0
0
0
0
0
0
0
0
0
0
0
0
0
0
15.5
14.4
15.6
12.6
12.9
15.6
17.6
16.5
13.1
11.5
10.1
13.3
17.8
13.8
29.4
30.5
31.0
31.2
31.1
31.7
29.6
31.2
30.3
31.7
32.5
31.3
30.6
31.5
44.9
44.9
46.6
43.8
44.0
47.3
47.2
47.7
43.4
43.2
42.6
44.6
48.4
45.3
BTT-C4
BTT-C6
BTT-C8
BTT-C10
BTT-C1-Ph
BTT-C1-NaPh
Another peak is also present during the forward scan, indicative of
the reaction 2 H2O → O2 (bubbles) + 4 H+ + 4 e– but starts only
at ≈ 2.0 V.
solutions free of monomers in order to better determine the ox-
idation and reduction potentials (Fig. 2 and Supporting Informa-
tion). For example, the oxidation potential of the polymer surfaces
in very close to that of the monomer (Table 2) and the effect of the
Then, the monomers were added and their oxidation potential
(Eox) was found to be both depending on the substituent and the
presence of ketone (Table 1). Then, cyclic voltammetry (from −1 V
to Eox) was chosen as the electropolymerization method. It is ex-
pected especially the release of H2 bubbles during the back scans
but also a lower amount of O2 bubbles during the forward scans.
Examples of cyclic voltammograms in CH2Cl2 are given in Fig. 1.
The polymer surfaces were also electrochemically characterized in
substituent is slight (1.89 V < Eox
< 2.00 V). These results
polymer
are similar to that obtained monomers highly favouring π-stacking
interactions such as with pyrene-based monomers, for which
the coatings containing both ultra-short oligomers and monomer
[32–34].
In CH2Cl2 + H2O, the cyclic voltammograms are relatively close
expected the presence of a very intense peak between 0 and −1 V
9

Y. Levieux-Souid, A. Sathanikan, F. Orange et al.
Electrochimica Acta 369 (2021) 137677
Fig. 8. SEM images obtained with BTT-C1-Ph in CH2Cl2 + H2O. 1, 3 and 5 scans at a scan rate of 20 mV s−1. The substrates are not inclined (on the left) and inclined at 45°
(on the right).
only during the back scans confirming the release of H2 bubbles
from H2O.
anhydrous CH2Cl2 and acetonitrile, and the presence of nanofibers
was observed especially in CH2Cl2 [35].
For the effects on the surface structures, first the influence of
the solvent (CH2Cl2 or CH2Cl2 + H2O) was studied by SEM using
only BTT-CO-C3 and BTT-C4. In CH2Cl2, the surfaces obtained with
BTT-CO-C3 have a low roughness, are inhomogeneous and with
some nanoparticles (Fig. 3). With BTT-C4, the surfaces are homo-
geneous with huge microdomes even if no open structures such as
nanotubes are observed. It is worth noting that electrodeposition
of unsubstituted BTT was already reported in literature [35–37] in
By contrast, the surfaces obtained in CH2Cl2 + H2O contain
a much higher number of porous structures (Fig. 3). Therefore,
the effect of the substituent and the presence of ketone was per-
formed especially in CH2Cl2 + H2O. Here, also the surfaces ob-
tained with the monomers with ketone groups are not extremely
homogeneous (Figs. 4 and 5). The monomer with an ultra-short
alkyl chain BTT-CO-C1 leads to a huge number of vertically aligned
tubules but most of the tubes formed are close. Then, the in-
10

Y. Levieux-Souid, A. Sathanikan, F. Orange et al.
Electrochimica Acta 369 (2021) 137677
Fig. 9. SEM images obtained with BTT-C1-Ph in CH2Cl2 and CH2Cl2 + H2O 50%. 3 scans at a scan rate of 20 mV s−1
.
Fig. 10. EDX spectra of polymer surfaces obtained with BTT-C1-Ph and BTT-CO-Ph in Bu4NClO4 / CH2Cl2 + H2O. 3 scans at a scan rate of 20 mV s−1
.
Fig. 11. IR spectra of polymer surfaces obtained with BTT-C1-Ph and BTT-CO-Ph in Bu4NClO4 / CH2Cl2 + H2O. 3 scans at a scan rate of 20 mV s−1
.
crease in the alkyl chain length changes the surfaces structures
from close nanotubules to nanoporous membranes (BTT-CO-C3)
and after the porosity decreases with the alkyl chain length. With
aromatic groups (BTT-CO-Ph and BTT-CO-NaPh) nanotubules are
formed but with BTT-CO-NaPh the majority of the tubes formed
are open and the surfaces are more homogeneous.
close structures are observed with ultra-short alkyl chain BTT-C2
but their height is relatively small. Then, a change from spherical
structures to nanoporous membrane is also observed as a function
of the alkyl chain length passing through nanorings with BTT-C4.
Unique results are obtained with aromatic groups (BTT-C1-Ph,
BTT-C1-NaPh) as already reported in the literature with thieno
[3,4-b]thiophene derivatives, for example (Fig. 6). Densely packed
huge open spheres are formed with these monomers. Their mean
diameter is roughly ≈ 2–3 μm and their thickness ≈ 0.5 μm. The
By contrast, extremely homogeneous surfaces are obtained with
the monomers without ketone confirming the importance to do
the ketone reduction (Figs. 6 and 7). Both spherical, tubular and
11

Y. Levieux-Souid, A. Sathanikan, F. Orange et al.
Electrochimica Acta 369 (2021) 137677
Fig. 12. SEM images obtained with BTT-C2, BTT-C4, BTT-C6, BTT-C8, BTT-C1-Ph and BTT-C1-NaPh in CH2Cl2 + H2O. 100 mC cm−2
.
study as a function of the number of scans (Fig. 8) shows that
more than 1 scan are necessary to produce these huge spheres
confirming the necessity to release of high amount of gas. Here,
the polymer growth is clearly three-dimensional (3D). Compared to
previous works [21,23,32,33], densely packed hollows were never
reported compared to vertically aligned nanotubes, even if thieno
[3,4-b]thiophene derivatives with pyrene substituents gave rela-
tively close results but less ordered. Moreover, just a phenyl group
is sufficient compared to other works with PheDOT, NaphDOT and
thieno [3,4-b]thiophene because benzotrithiophene is already ex-
tremely aromatic.
moieties. Indeed, it was demonstrated that even the position of the
substituent can highly affect the polymer growth [24].
In order to better estimate the influence of H2O content, BTT-
C1-Ph was electropolymerized not only in CH2Cl2 but also in
CH2Cl2 + H2O diluted 50% vs CH2Cl2, called CH2Cl2 + H2O 50%.
SEM images (Fig. 9) show that in CH2Cl2 the surfaces are rela-
tively smooth with just some wrinkles while in CH2Cl2 + H2O 50%
the surfaces contain spheres of smaller size and most of them are
close.
The surfaces were characterized by optical profilometry to de-
termine their surface roughness, surface area as well as the rough-
ness parameter (r) of the Wenzel equation [40] (Table 2). By cyclic
voltammetry, the surface roughness is extremely high even after
just one deposition scan, which is expected due to the release of
Hence, the presence of a ketone group leads to less ordered
surfaces. This fundamental result may be explained by a decrease
of interactions (especially π-stacking) between benzotrithiophene
12

Y. Levieux-Souid, A. Sathanikan, F. Orange et al.
Electrochimica Acta 369 (2021) 137677
Table 5
Wettability data for the polymer films obtained
–
at constant potential from BTT-C1 NaPh.
Deposition charge [mC cm−2
]
θw [deg]
12.5
25
73.1
94.0
99.6
94.4
64.0
0
1.1
5.9
5.0
3.2
5.8
50
100
200
400
a high amount of H2 bubbles. After one deposition scan, the high-
est roughness is obtained with BTT-CO-Ph and BTT-CO-C1 and the
lowest roughness with BTT-CO-C5, BTT-CO-C7 and BTT-C8.
The surfaces were also chemically characterized by EDX and
infrared. The EDX analyses (Fig. 10) show for the substrate the
presence of Au (95.3 mass%), C (4.2 mass%) and O (0.5 mass%).
It was not possible to distinguish the monomers with or without
ketone because it is observed the presence of remaining perchlo-
rate (ClO4−) counterions. For example, for BTT-C1-Ph it was found
C (52.2 mass %), O (10.3 mass %), S (19.3 mass %), Cl (2.6 mass %)
and Au (15.6 mass %) while for BTT-CO-Ph there is C (63.3 mass %),
O (11.4 mass %), S (17.9 mass %), Cl (5.0 mass %) and Au (2.4 mass
%). For the IR spectra, peaks are present for example at ≈ 2800–
3000 cm−1 for C–H stretching, 1500–1700 cm−1 for C=C stretch-
ing, 1100–1300 cm−1 for C–S stretching and C=C bending (Fig. 11).
The study of their surface hydrophobicity shows that θw is
extremely varied with a maximum of 109.4° for BTT-CO-NaPh
(Table 3). The surfaces with densely packed huge open spheres ob-
tained with BTT-C1-Ph are slightly hydrophilic and it is observed a
slight increase of θw with the number of deposition scans.
In order to better explain the wettability results, it was very im-
portant to prepare smooth polymers. Table 4 shows that all these
smooth polymers are intrinsically hydrophilic whatever the sub-
stituent with Young’s angle [38] with water 59.4° < θY,w < 70.5°
and surface energy, determined with the Owens Wendt equation
[39], 42.6 mN m−1 < γ S < 48.4 mN m−1. The monomers without
ketone often leads to more hydrophobic surfaces, as expected due
to its high polarity. The hydrophobicity increases with the alkyl
chain length until n = 8 and decreases after because the surface
becomes saturated. BTT-C1-NaPh leads also to more hydrophobic
surfaces than BTT-C1-Ph.
Using all the monomers without ketone, another deposi-
tion method is also tested: the deposition at constant potential
(E = Eox). In this method, only O2 bubbles can be released even if
their number should be low because the monomer oxidation po-
tential is close to that of H2O. SEM images for a deposition charge
(Qs) of 100 mC cm−2 are gathered in Fig. 12. Here, nanotubular
structures and nanoporous surfaces are also mainly observed.
Using BTT-C1-NaPh, vertically aligned nanotubes are formed
(Fig. 13). With this electrodeposition method, it is observed the
presence of nanopores for Qs = 12.5 mC cm−2 before the forma-
tion of nanotubes. Most of the tubes are open with short Qs up
to 50 mC cm−2. Then, the nanotubes become close at higher Qs.
Moreover, it is also observed an increase in the size of the tubes
with Qs. For the wetting properties (Table 5), it is also observed an
increase of θw up to 99.6° for Qs = 50 mC cm−2 and a decrease
after because the nanotubes became close. Hence, when a droplet
is on a surface made with Qs = 50 mC cm−2, the amount of air be-
tween the surface and a water droplet is the highest because it is
energetically difficult to wet inside the open nanotubes even if the
material is intrinsically hydrophilic. This is an intermediate state
between the Wenzel and the Cassie-Baxter state [40–45].
Fig. 13. SEM images obtained with BTT-C1-NaPh in CH2Cl2 + H2O from 12.5 to 400
mC cm−2
.
At constant potential, the surfaces surface roughness and sur-
face area are given in Table 6. Here, the surfaces are less rough
13

Y. Levieux-Souid, A. Sathanikan, F. Orange et al.
Electrochimica Acta 369 (2021) 137677
Table 6
than the surfaces by cyclic voltammetry because only small
amount of O2 bubbles can be released. An increase of the surface
roughness is observed but especially after from 100 mC cm−2. Af-
ter 400 mC cm−2, the lowest roughness is observed with BTT-CO-
NaPh, BTT-C2, BTT-C4 and BTT-C1-NaPh.
Arithmetic (Ra) and quadratic (Rq) surfaces roughness, surface area (for an analysed
surface of 0.275 mm2) and roughness parameter (r) of Wenzel equation, for the
surfaces obtained at constant potential in CH2Cl2+ H2O.
Number of
Surface
deposition charge
−2
area
2
Monomer
[mC cm
]
Ra [μm]
Rq [μm]
[mm
]
r
BTT-
CO-
12.5
25
0.02
0.03
0.05
0.37
0.52
1.0
0.01
0.03
0.04
0.06
0.58
0.74
2.1
0.01
0.275
0.275
0.275
0.360
0.432
0.667
0.275
0.275
0.275
0.315
0.391
0.431
0.275
0.275
0.275
0.390
0.330
0.620
0.275
0.275
0.275
0.958
1.16
1.0
1.0
1.0
1.3
1.6
2.4
1.0
1.0
1.0
1.2
1.4
1.6
1.0
1.0
1.0
1.4
1.2
2.3
1.0
1.0
1.0
3.5
4.2
4.0
1.0
1.0
1.0
1.2
1.7
2.6
1.0
1.0
1.0
1.0
1.0
1.1
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.2
1.6
1.9
1.0
1.0
1.0
1.1
1.2
3.6
1.0
1.0
1.0
1.1
4.1
4.2
1.0
1.0
1.0
1.0
1.6
3.0
1.0
1.0
1.0
1.0
1.6
1.9
1.0
1.0
1.0
1.1
1.1
1.1
Conclusion
0.01
0.01
0.05
0.10
0.01
0.01
0.09
0.12
C
1
50
In this original work, we investigated benzotrithiophene-based
monomers by soft template electropolymerization. We have shown
how to obtain extremely ordered porous surface structures of
different shape. We tested different parameters such as the na-
ture of the substituent, the presence of a ketone group between
the monomer and the substituent, the water content and the
electropolymerization method. Unique results are obtained with
the monomers without ketone and with aromatic substituents
(phenyl and naphthalene), which lead to densely packed huge open
spheres by cyclic voltammetry and in dichloromethane saturated
with water. These surfaces could be used for a wide range of ap-
plications such as in water harvesting systems, drug delivery or in
catalyst.
100
200
400
12.5
25
0.1
0.2
BTT-
CO-
0.07
0.08
0.08
0.26
0.40
0.68
0.03
0.04
0.04
0.24
0.42
1.2
0.01
0.02
0.02
0.04
0.05
0.12
0.01
0.01
0.01
0.05
0.09
0.10
0.17
0.13
0.42
0.54
0.90
0.04
0.06
0.05
041
0.76
1.7
0.01
0.03
0.02
0.10
0.09
0.15
0.01
0.01
0.01
0.12
0.16
C
3
50
100
200
400
12.5
25
BTT-
CO-
C
5
50
100
200
400
12.5
25
0.2
0.3
BTT-
CO-
0.02
0.02
0.05
1.4
0.01
0.01
0.01
0.03
0.03
0.06
1.8
0.01
0.01
0.01
C
7
50
100
200
400
12.5
25
0.1
0.2
Declaration of Competing Interest
The group declares no conflict of interest.
Acknowledgments
1.5
0.1
0.3
2.1
0.2
0.4
2.4
3.1
1.10
BTT-
CO-
Ph
0.03
0.04
0.10
0.49
0.94
1.6
0.01
0.06
0.06
0.14
0.60
1.4
0.01
0.275
0.275
0.275
0.341
0.466
0.702
0.275
0.275
0.275
0.281
0.281
0.290
0.275
0.275
0.275
0.275
0.275
0.282
0.275
0.275
0.275
0.320
0.444
0.521
0.275
0.275
0.275
0.300
0.343
1.00
0.01
0.02
0.06
0.20
0.01
0.03
0.09
50
100
200
400
12.5
25
0.3
0.6
0.01
0.4
2.4
The group thanks Christelle Boscagli from the Centre Commun
de Microscopie Appliquée (CCMA, Université Côte d’Azur) for the
preparation of the substrates necessary for the SEM analyses. IR
analyses were performed at the Smart City Innovation centre (Uni-
versité Côte d’Azur, IMREDD). The “Smart City Innovation cen-
tre” is a project funded by the European union with the Euro-
pean fund for regional development and co-funded by Métropole
Nice Côte d’Azur, the département Alpes-maritimes, the région Sud
Provence-Alpes-Côte and France for the “initiative d’excellence”
(Investissements d’avenir). This work has been supported by CNRS
GDR 2088 « BIOMIM ».
BTT-
CO-
0.02
0.04
0.04
0.21
0.21
0.35
0.04
0.05
0.05
0.12
0.10
0.24
0.04
0.03
0.06
0.24
0.38
0.42
0.05
0.05
0.06
0.14
0.23
1.8
0.03
0.01
0.01
0.02
0.02
0.04
0.01
0.01
0.01
0.03
0.02
0.04
0.01
0.01
0.01
0.04
0.06
0.8
0.04
0.05
0.05
0.29
0.31
0.45
0.06
0.07
0.07
0.15
0.13
0.30
0.05
0.05
0.07
0.46
0.63
0.75
0.06
0.09
0.09
0.48
0.47
2.9
0.01
0.01
0.03
0.03
0.05
0.01
0.01
0.01
0.04
0.02
0.06
0.01
0.01
0.01
0.05
0.08
0.13
0.01
0.01
0.01
0.03
0.10
NaPh
50
100
200
400
12.5
25
BTT-
C
2
50
100
200
400
12.5
25
BTT-
C
4
50
100
200
400
12.5
25
Author contribution
Yanis Levieux-Souid and Ananya Sathanikan did the monomer
synthesis and surface characterization, François Orange did the EDX
analyses, Thierry Darmanin did the electropolymerization process.
Thierry Darmanin and Frédéric Guittard did the discussion part
and wrote the manuscript.
BTT-
0.01
0.01
0.01
0.02
0.05
C
6
50
100
200
400
12.5
25
0.3
0.5
BTT-
0.02
0.03
0.03
0.44
1.7
0.01
0.01
0.01
0.08
0.04
0.04
0.06
0.75
2.2
0.01
0.01
0.01
0.09
0.275
0.275
0.275
0.301
1.12
C
8
Supplementary materials
50
100
200
400
12.5
25
0.1
0.1
0.01
0.2
0.2
0.01
Supplementary material associated with this article can be
found, in the online version, at doi:10.1016/j.electacta.2020.137677.
1.9
2.5
1.15
BTT-
0.02
0.04
0.05
0.05
1.0
0.02
0.06
0.06
0.06
1.3
0.275
0.275
0.275
0.275
0.430
0.835
0.275
0.275
0.275
0.281
0.437
0.510
0.275
0.275
0.275
0.305
0.306
0.292
C
0.01
0.01
0.01
0.01
0.01
0.01
10
50
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100
200
400
12.5
25
0.1
0.1
0.01
0.2
0.2
0.01
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