the benzoate-Ag moieties in the synthesized networks, the crystal structure of silver benzoate has also been analyzed. Also in this case, to reproduce the EXAFS ...
Supporting Information On the Dimensional Control of 2 D Hybrid Nanomaterials Alessandro Longo,[a, b] Dirk-Jan Mulder,[c, d] Huub P. C. van Kuringen,[c, d] Daniel HermidaMerino,[a] Dipanjan Banerjee,[e] Debarshi Dasgupta,[c] Irina K. Shishmanova,[c] Anne B. Spoelstra,[h] Dirk J. Broer,[c, f] Albert P. H. J. Schenning,*[c, f] and Giuseppe Portale*[g]
chem_201701493_sm_miscellaneous_information.pdf
Supporting Information
Characterization techniques X-Ray Diffraction (XRD). XRD of monomer mixtures was measured on samples sealed in a 1 mm glass capillary, inserted in 1 Tesla magnetic field inside a heating stage using monochromatic Cu-kα source ( = 1.54 Å, Philips) and a Siemens Hi-Star area detector. The temperature was controlled using a Linkam hotstage TMS-94 controller and the patterns were collected during the second cooling run applied to the material. Polarization Optical Microscopy (POM). POM studies were conducted using a Leica CTR 6000 microscope equipped with two polarizers that were operated either crossed or parallel with the sample in between a Linkam hot-stage THMS-600 controlled by a Linkam TMS-94 controller and a Leica DFC420 C camera. Differential scanning calorimetry (DSC). DSC measurements were performed in hermetic T-zero aluminum sample pans under nitrogen atmosphere using TA Instruments Q1000 DSC equipped with a RCS90 cooling accessory. All the samples containing non-polymerized monomers were doped with 0.1 wt. % inhibitor (p-methoxy phenol) to prevent temperature induced polymerization. The DSC experiments were conducted at a rate of 5 °C/min and the transition temperatures were determined from the second heating/cooling run using Universal Analysis 2000 software (TA instruments, USA). Thermogravimetric analyses (TGA). TGA were performed on a TA Instruments Q500 TGA in a nitrogen atmosphere till 200 °C followed by an isotherm for 15 minutes in the same atmosphere and subsequently in air atmosphere until 800 °C. Samples were heated at a rate of 10 °C/min. Fourier transform infrared (FTIR). FTIR measurements were performed using a Varian Excalibur 3100 spectrometer equipped with a Specac Golden Gate diamond ATR. Spectra were obtained using 4 cm-1 resolution and 100 scans were co-added for both the sample and the background. Extended X-ray absorption fine structure (EXAFS) analysis. Three EXAFS scans of 1 hour each have been collected per each sample. The EXAFS spectra were energy-calibrated, averaged and further analyzed using GNXAS.1,2 In this approach, the local atomic arrangement around the absorbing atom is decomposed into model atomic configurations containing 2, 3,
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..., n atoms. The theoretical EXAFS signal χ(k) is given by the sum of the two-body γ2, γ3, ..., γn, and 2, 3, ..., n three-body contributions respectively which take into account all the possible single and multiple scattering (MS) paths between the n atoms. The fitting of χ(k) to the experimental EXAFS signal allows to refine the relevant structural parameters of the different coordination shells. The suitability of the model is also evaluated by comparison of the experimental EXAFS signal Fourier transform (FT) with the FT of the calculated χ(k) function. The fit parameters that were allowed to vary during the fitting procedure were the coordination numbers N, the distances R(Å), the Debye-Waller factors (σ2) and the angles of the n contributions. The threshold energy Ek = 0 was defined at 25514 eV. The experimental k*χ(k) signal for a standard Ag2O powder (cubic structure Pn-3m with lattice parameter a equal to a = 4.723 Å ) was well reproduced by using only two single scattering contributions 2 relative to the first coordination shell made of 2 oxygen atoms at 2.05 Å and the second coordination shell made up of 6 Ag atoms at 3.33 Å. Due to the similar chemical structure of the benzoate-Ag moieties in the synthesized networks, the crystal structure of silver benzoate has also been analyzed. Also in this case, to reproduce the EXAFS signal only two single scattering contributions 2 relative to the first coordination shell made of 2 oxygen atoms at a distance of about 2.10 Å and the second coordination shell made up of 1 Ag atom at 2.68 Å were used. Regarding the silver nanoparticles, two 2 terms taking into account the first and second coordination shell were used considering that the silver metal clusters have a fcc lattice. The first-shell Ag−Ag distance (R1) is linked to the fcc a-axis length by R1 = a/21/2, while the second neighbors are placed at a distance R2. The higher shells were calculated according to three-body contributions 3: the third shell term (R3), at R3 = 31/2a/2, is according to an isosceles triangle with two first neighbors representing the R1 sides and a vertical angle θ = 120°. The fourth shell contribution (R4), involving particularly strong multiple scattering contributions, is obtained from the degenerate (θ = 180°) triangle formed by three aligned first neighbors. Consequently, the lattice constant a and the Debye−Waller factor (σ2) were the only parameters used in the fit to calculate the Ag metal environment. Gracing incidence small angle X-ray scattering (GISAXS). GISAXS measurements were performed at the BM26B-DUBBLE beam line at the ESRF. An X-ray wavelength of = 0.1 nm was used with 2m and 4m sample-to-detector distances. GISAXS images were recorded using a high sensitive solid state silicon photon counting Pilatus 1M detector with pixel size of 172x172 m and active surface dimension of 179x169
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mm. Simulations of the GISAXS images and profiles were calculated using the IsGISAXS software3 with one or two populations of spheroidal objects with average radius R. Polydispersity was taken into account using a Gaussian function to describe the distribution in the radii.
References (1) Filipponi, A.; Di Cicco, A. X-Ray-Absorption Spectroscopy and N-Body Distribution Functions in Condensed Matter. II. Data Analysis and Applications. Phys. Rev. B 1995, 52 (21), 15135. (2) Filipponi, A.; Di Cicco, A.; Natoli, C. R. X-Ray-Absorption Spectroscopy and N-Body Distribution Functions in Condensed Matter. I. Theory. Phys. Rev. B 1995, 52 (21), 15122. (3) Lazzari, R. IsGISAXS: A Program for Grazing-Incidence Small-Angle X-Ray Scattering Analysis of Supported Islands. J. Appl. Crystallogr. 2002, 35 (4), 406–421.
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Tables
Table S1 Phase behavior of the LC mixtures based on DSC data. LC mixture
T, °C [a]
6OBA
Cr
91
Sm A
100
N
109
I
Cr2
90
Sm A
100
N
110
I
Cr
90
Sm A
97
N
106
I
Cr2
89
Sm A
97
N
109
I
6OBA+C6 [b]
Cr1
69
6OBA+C11 [b] 6OBA+C3 [b] [a]
Cr1
65
Temperatures are reported based on the second DSC heating run (5 °C/min). The observed
phases are identified by following abbreviations: Cr = crystalline, SmA = smectic A, N = nematic, I = isotropic liquid. [b] The ratio 6OBA/crosslinker is 90/10 w/w.
Table S2. EXAFS results of the Ag+ polymer salt films. C3
C6
C11
Ag2O
AgBenzoate
N1
2.0(0.5)
2.0(0.5)
2.0(0.5)
2.0
2.0
R1
2.195
2.195
2.189
2.0326
2.10
(0.005)
(0.005)
(0.005)
1
0.0042(1)
0.0032(3)
0.003(3)
0.0026
0.002
N2
1.8(0.6)
1.8(0.6)
2.2(=.4)
6.0
1.0
R2
2.797(5)
2.797(5)
2.815(6)
3.334
2.680
2
0.0048(3)
0.0048(3)
0.0048(4)
0.0052
0.0058
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Table S3. EXAFS results for the silver nanoparticle polymer films. The angle value is reported in (°) C3
C6
C11
Ag foil
N1
6.(0.7)
8.0(0.7)
9.0(0.7)
12
R1
2.858 (0.005)
2.865(0.005)
2.870(0.005)
2.877
1
0.0025(3)
0.0027(3)
0.0022(2)
0.0029
N2
3.(0.7)
4.(0.7)
4.7(0.7)
6
R2
4.04(0.01)
4.06(0.01)
4.06(0.01)
4.050
2
0.0027(2)
0.0079(1)
0.0064(3)
0.0054
N3
12.(0.9)
13.4(0.9)
16.(0.9)
24
1
120.(3)
118.(2)
120.(2)
120.
(R3=5.00)
(R3=5.000)
(R3=5.004)
(R3=4.999)
3
0.0061(2)
0.0064(3)
0.0057(3)
0.0050
N4
4.0(0.9)
4.2(0.9)
5.2(0.9)
12.
2
178.(4)
180.(4)
180.(4)
180.1
(R4=5.751) 4
0.0049(3)
(R4=5.751)
(R4=5.751)
0.0053(4)
0.0044(3)
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(R4=5.753) 0.0059
Figures
95 °C
23 °C
6OBA + C3H
6OBA + C11H
6OBA + C6H
6OBA
105 °C
Figure S1. POM micrographs of pure monomer 6OBA and the mixtures 6OBA+C6 (90/10 w/w), 6OBA+C11 (90/10 w/w) and 6OBA+C3 (90/10 w/w) during cooling from the isotropic melt. Scale bar 100 µm.
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Heating
Cooling
g-1) Heatflow Heatflow(W (W/g)
6OBA 6OBA + C6
6OBA + C11 6OBA + C3
60
80
40
100
60
80 100
Temperature ((C) Temperature C)
Figure S2. DSC traces during the second heating and cooling cycle of pure monomer 6OBA and the mixtures 6OBA+C6 (90/10 w/w), 6OBA+C11 (90/10 w/w) and 6OBA+C3 (90/10 w/w) (endothermic up, rate 5 °C/min).
6OBA 6OBA
6OBA + C3 6OBA + C6H
+ C6 6OBA6OBA + C11H
6OBA + C11 6OBA + C3H
Intermolecular distance Layer spacing
Figure S3. X-ray diffraction images for the pure 6OBA and the 6OBA/cross-linker blends at 85 °C. The magnetic field is oriented horizontally.
S7
500 C11 wet
Intensity (a.u.)
400
C11 dry
300 200 100 0 0
1
2
3
4
-1
5
q (nm )
Figure S4. SAXS intensity for the C11 membrane in the open pore wet state (Na+ salt form). The SAXS peak appears shifted with respect to the one in the dry state, as a result of water incorporation inside the network. Water incorporation induced a more disordered structure, as evidenced by the absence of clear higher order reflections. The peak shifts from about 3.3 nm to 4.5 nm, suggesting that the pore size increases from 1 nm in the dry state to about 2 nm in the swollen state.
100
Weight (%)
Weight (%)
80
60
40
20
0
100
Temperature ( C)
200
300
400
500
600
o
Temperature ( C)
Figure S5. (Top) TGA traces of 6OBA/C6 Ag+ and 6OBA/C11 Ag+ polymer films. (Bottom) TGA traces of 6OBA/C6 polymer film (solid line) and the corresponding 6OBA/C6 Ag+ polymer silver salt film (open circles). The obtained relative residue content for the silver containing polymer is 28%, which is in close agreement with the theoretical 32% content assuming full complexation of carboxylate groups (one silver atom per 6OBA monomer)
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Ag 3d
O 1s
Ag 3p C 1s
Ag 3s C KVV O KLL Ag MVV Na 1s
Na KLL Si 2p Si 2s Ag 4d Ag 4p
374
3d3/2 = 374.05 eV
373
B.E. (eV)
372 371 370 369 368
3d5/2 = 368.08 eV
367 366 365 0
50
100
150
200
250
300
350
Sputtering Time (min)
Figure S6. A) XPS survey scan of the 6OBA/C6 Ag+ polymer silver salt film. B) XPS depth profile of the 6OBA/C6 Ag+ polymer film, showing the Ag 3d region. Spectra are plotted top to bottom as function of the sputter-time/depth. C) Corresponding variation of Ag+ binding energies as a function of sputtering time (depth from film surface).
S9
B
k2 c(k)
A
k (Å-1)
C
R (Å)
R
R
R
R
Figure S7. A) Experimental and calculated EXAFS signals for the Ag+/LC polymeric networks. B) Corresponding Fourier transforms for the Ag+/LC polymeric networks. Data from standard Ag2O and silver benzoate (AgBz) have been also recorded and are reported for comparison. C) Local structure for the Ag-carboxylate dimers as obtained by EXAFS analysis. Grey spheres = silver, red spheres = oxygen and brown spheres = carbon atoms. Note that the relative position of the two dimers is arbitrary, as the molecules inside the layers do not show crystalline order.
S10
+
Na form
Intensity (a.u.) Intensity (a.u.)
+
Ag form
0
5
10 -1 q (nm-1)
15
20
q (nm ) Figure S8. Integrated scattered intensity for Na+ and Ag+ form of the supported C11 network. Layer spacing are indicated by symbols and are equal to 3.4 nm and 2.9 nm for the Na+ and Ag+ salt film, respectively.
B
k c(k)
A
k (Å-1)
Energy (ev)
Figure S9. A) XANES signal for the networks in the Ag+ salt form (broken lines) and after chemical Ag reduction (solid lines). Black curve are data for a standard Ag foil. B) Experimental and calculated EXAFS signals for the Ag NPs LC hybrid networks.
S11
375 374
3d3/2 = 373.85 eV
373
B.E. (eV)
372 371 370 369 368
3d5/2 = 367.88 eV
367 366 365
0
50
100
150
200
250
300
350
Sputtering Time (min)
Figure S10. a) XPS depth profile for the 6OBA/C6 polymer silver nanoparticle film, showing the Ag 3d region. Spectra are plotted top to bottom as function of the sputter time/depth. b) Variation of Ag0 binding energies as a function of sputtering time (depth from film surface) in the 6OBA/C6 polymer silver nanoparticle film.
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Absorbance (a.u.)
a)
1800
1600
1400
1200
1000
800
-1
Wavenumber (cm )
Absorbance (a.u.)
b)
1800
1600
1400
1200
1000
800
1000
800
-1
Wavenumber (cm )
Absorbance (a.u.)
c)
1800
1600
1400
1200 -1
Wavenumber (cm )
Figure S11. a) FT-IR spectra for the 6OBA/C6 polymer films before (solid line) and after (dotted line) NaOH treatment showing the disappearance of the vibrational peak located at 1673 cm-1 (C=O stretching of the carboxylic acid dimers) and the appearance of the 1532 cm1 (antisymmetric COO- stretching for the Na+ salt), and 1385 cm-1 (symmetric COO- stretching) vibrational peaks; b) FT-IR spectra for the 6OBA/C6 polymer films after NaOH treatment (solid line) and after AgNO3 treatment (dotted line) showing vibrational peaks at 1532 cm-1 (antisymmetric COO- stretching for Na+ salt) and 1504 cm-1 (antisymmetric COO- stretching for Ag+ salt), respectively; c) FT-IR spectra for the 6OBA/C6 polymer films after AgNO3 treatment (solid line) and after NaBH4 treatment (dotted line) revealing vibrational peaks at 1544 cm-1 (antisymmetric COO- stretching for Na+ salt) and 1504 cm-1 (antisymmetric COOstretching for Ag+ salt) respectively.
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A
B
C
D
E
Counts
F
Particle size (nm)
Figure S12. A-C) Multiple images of the small Ag NPs observed in the bottom part of the hybrid film with C11 cross-linker. D-F) Estimation of the NPs size distribution for the C11 sample. D) Enhanced image. E) Particle counting process. F) Calculated size distribution from image F.
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B
20 nm
f (°)
Figure S13. TEM images of the silver nanoparticle/polymer hybrid film having a C6 crosslinker. A) At the surface region, and B) in the bulk of the film.
f (°) Figure S14. GISAXS image for the silver nanoparticle polymer film having a C11 cross-linker supported on glass. The incident angle is i = 0.25°. The image has been acquired using a sample-to-detector distance of 2m.
S15
f (°)
f (°)
f (°)
f (°)
Figure S15. A) Measured GISAXS image of the Ag NP/polymer hybrid film with the C11 cross-linker acquired at i = 0.2°. B) Simulated GISAXS image from a bimodal ensemble of spherical Ag NPs with averaged dimensions of 11 and 5 nm and relative abundance of 16% and 84%, respectively. Simulations have been accomplished using the IsGISAXS software.
pH 10
Figure S16. Optical micrographs showing the anisotropic swelling of a smectic polymer film having a C6 cross-linker placed in an alkaline solution at pH = 10. Scale bar is 500 micrometer.
S16
