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Study and development of localised surface plasmon resonance based sensors using anisotropic spectroscopy
Presented by Mr. William L. Watkins
Supervised by Dr. Yves Borensztein
October the 8th, 2018
Jury members
PR. CHRISTOPHE PETIT Professeur Président
DR. HYND REMITA Directrice de recherche Rapporteur
DR. LIONEL SIMONOT Maître de conferences Rapporteur
DR. RAMDANE BENFERHAT Directeur de stratégie Examinateur
PR. DIDIER GOURIER Professeur Examinateur
DR. VIRGINIE PONSINET Chargée de recherche Examinateur
Ecole doctorale : Physique et chimie des matériaux – ED397Laboratoire : Institut des nanosciences de ParisEquipe : Physico-chimie et dynamique des surfaces
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
2
2019 à Pau
� “Hydrogen economy”, energy of the future?
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
Embedded system
Electrical risks
3
� Need for H2 sensors
Explosive range
4% 70%
Pure H2Pure air
� Highly explosive in air
Hübert, T., et al. (2011). Sensors and Actuators B: Chemical, 157(2), 329–352.
Solution
Development of opticalsensing
����� � 2 → 2�
Formation of Palladium hydride
Best optical sensitivity
0.1% in N20.5% in air
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
4
Use anisotropic plasmon as an optical method for high sensitivity sensing
� Objectives and motivations
H2 sensing with PdSurface interaction of
H2 with Au NP
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
5
3. Fundamental study : surface interaction of H2 with Au
o Experimental insight into the mechanismo Determination of the charge transferred
2. Fabrication of anisotropic samples
o Fabrication of Au sampleso Model the spectrao Optimising the anisotropy
4. Application study : sensing of H2 with LSPR
o Need for better optical sensing o Use of Au and Pd sensorso Use of pure Pdo Increase in sensitivity
1. LSPR fundamentals
o LSPR for sensingo Anisotropy in LSPRo Anisotropy spectroscopy
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
6
� Properties of metals at the nanoscale
Localised surface plasmon resonance (LSPR)
Definition: collective oscillation of conduction electron excited by an oscillating electric field
525 nm
Absorption in the case of Au in the Visible
Nanogold suspension
� �� ∝ �����
Abs cross-section Polarisability
������� � 3�� � ��
� � 2��
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
7
� LSPR shift : Change in the medium
Increase in εm leads to red shift
������� � 3�� � �
� � 2�
∆"
LSPR used as sensors
o
NP
Adsorbed entities
Medium εm
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
8
� LSPR shift : Charge transfers
������� � 3�� � ��
� � 2��
∆"
o
NP
Adsorbed entities
Material ε
e-
��#� � 1 �%&2
#�# � '(�1�� �') �#�
Drude model
N : conduction electron density
Decreases in N leads to red shift
LSPR used surface reactivity study
1
2
∆*
*+ �
∆",���
",���
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
∆"
abs
9
Spectral measurement
Curve fitting(ex: Gaussian fit)
Technique : UV-Vis spectroscopy
Easy for large shifts Hard for small shifts
∆"
� Measuring the shift : conventional technique
Issues
Absolute
• Sensitive to fluctuations : light, pollution, vibration
• Needs reference
Spectral
• Requires monochromator• Needs fitting of the curve
Monochromator
• Compromise : resolution & bulkiness
Use of anisotropy to solvethese issues
abs
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
B
A
10
Ellipsoid
MICROscopy anisotropy
Two maxima for the two orthogonal polarisations
A
B
� Anisotropy in LSPR
������� � 3�� � ��
� � 2��
��,,-�. � �� � ��
�� � /�� � ���
Depolarisation Factor
MACROscopy anisotropy
Needs to be globallyanisotropic
A
B
Does not have to be perfect
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
B
A
11
� Use of Transmittance anisotropy spectroscopy
MACROscopy anisotropy
Needs to be globallyanisotropic
A
B
Does not have to be perfect
Solution : Anisotropic spectroscopy
� RAS (Aspnes)ReflectanceAnisotropySpectroscopy
� TASTransmittanceAnisotropySpectroscopy
Technique known and used
at INSPFor anisotropic metal
surface studies
Δ1
1
Absolute
DifferentialAspnes, D. E., et al (1988). Applied Physics Letters, 52(12), 957–959. Palummo, M., et al (2009). Phys. Rev. B, 79(3), 1–8. Vidal, F., et al (2006). Phys. Rev. B, 74(11), 1–7. Mazine, V., & Borensztein, Y. (2002). Phys. Rev. Let., 88(14), 147403. Borensztein, Y., et al (1993). Phys. Rev. Let., 71(14), 2334–2337.
23
345
26
6�67 869
6
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
12
� Use of Transmittance anisotropy spectroscopy
∆"
∆"
Δ1
1
Shift influences both peaks TAS shifts as well
Absolute
Differential
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
13
� Use of Transmittance anisotropy spectroscopy
∆"
Δ1
1 ∆"
∆:
Shift influences both peaks TAS shifts as wellCan now work at
single wavelength
Absolute
Differential
∆"
The steeper the better
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
14
� Use of Transmittance anisotropy spectroscopy
Δ1
1
• Better reproducibility
• Signal more stable
• Better sensitivity
• No need for
monochromator nor fitting
Relative & differential
Single wavelength
Issues
Absolute
• Sensitive to fluctuations : light, pollution, vibration
• Needs reference
Spectral
• Requires monochromator• Needs fitting of the curve
Monochromator
• Compromise : resolution & bulkiness
∆"
∆:
The steeper the better
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
15
3. Fundamental study : surface interaction of H2 with Au
o Experimental insight into the mechanismo Determination of the charge transferred
2. Fabrication of anisotropic samples
o Fabrication of Au sampleso Model the spectrao Optimising the anisotropy
4. Application study : sensing of H2 with LSPR
o Need for better optical sensing o Use of Au and Pd sensorso Use of pure Pdo Increase in sensitivity
1. LSPR fundamentals
o LSPR for sensingo Anisotropy in LSPRo Anisotropy spectroscopy
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
16
• Simple to synthesise
• Use non-expensive materials
• Large surface area samples (mm2)
• Small metallic nanoparticles (∅≃10nm)
• Global anisotropy of the sample
• Exposed nanoparticles
� Our requirements : scalability in mind
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
Nanoparticles
17
20 nm
17
� Known methods
Lithography
× Simple× Non-expensive× Large area× Small NPs� Anisotropic� Exposed
Zoric´, I., et al (2010). Advanced Materials, 22(41), 4628–4633.
Chemical synthesis
Li, J. et al. (2010). App. Phys. Let., 96(26), 263103.
� Simple � Non-expensive� Large area� Small NPs× Anisotropic× Exposed
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
18
× Simple× Non-expensive� Large area� Small NPs� Anisotropic� Exposed
R. Verre et al, (2016), Nanoscale, 8, 10576
L. Anghinolfi, et al, (2011), J. Phys. Chem., C115,14036
Sapphire monocrystal
LiF crystal
Oblique Angle Deposition on stepped surfaces
Method that inspired the thesis
Apply this method to simpler substrates
� Known methods
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
19
� Known methods: choice of OAD
=
Evaporation at grazing angle
Glass
Au
� Simple� Non-expensive� Large area� Small NPs� Anisotropic� Exposed
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
EXP
T
Dichroism
Anisotropic spectrum20
� Known methods: choice of OAD
A
B
Weak structural anisotropy
=
Evaporation at grazing angle
UV-Vis TASEvap. direction
SEM
Glass
Au
∅≃10nm
� Simple� Non-expensive� Large area� Small NPs� Anisotropic� Exposed
FFT
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
a2 a1
a3
Cal. Exp.
21
� Calculated with supported ellispoids
� Model the spectra
��,,-�. � �� � ��
�� � >�� � ���
Side view
?@ � 3.6nm
?� � 4.7nm
?F � 1.2nmG � 16H�
A
B para
Evap. direction
Top view
To scale
G
A perp
B
Model reproduces experiments
G
Barrera et al, (1991), Phys. Rev. B43, 13819
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
22
The angle controls the resonance wavelength
Working wavelength from 600nm to 800nm
The thickness controls the anisotropy (slope)
� Optimising the anisotropy
Evaporation parameters controls the shapeof the anisotropy
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
23
3. Fundamental study : surface interaction of H2 with Au
o Experimental insight into the mechanismo Determination of the charge transferred
2. Fabrication of anisotropic samples
o Fabrication of Au sampleso Model the spectrao Optimising the anisotropy
4. Application study : sensing of H2 with LSPR
o Need for better optical sensing o Use of Au and Pd sensorso Use of pure Pdo Increase in sensitivity
1. LSPR fundamentals
o LSPR for sensingo Anisotropy in LSPRo Anisotropy spectroscopy
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
24
Knowns
H2 molecules adsorb and dissociate on the edges on the Au NPs
Charge transfer from bulk to bond
N decreases then red shift
Illas. F, et al. (2007). Chem. Com. (32), 3371–3373.
Hu, M., et al. (2013). J. Phys. Chem. C, 117, 15050–15060.
� What is and isn’t known in the lit. ?
1
2
∆*
*+ �
∆",���",���
What is the becoming of the H after adsorption ?
Unknowns
DFT
DFT
What is the charge transfer ?
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
25
∆I
� What is and isn’t known in the lit. ?
H2 / Ar cycles on Au NP
Δ1
1
∆"
∆:
Reminder
Red shift
Watkins, W. L., & Borensztein, Y. (2017). PCCP., 19, 27397.
time
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
26
∆I
∆I
∆I
� What is and isn’t known in the lit. ?
H2 / Ar cycles on Au NP different size
JKL MNMO
Hypothesis : PQ ∝ JKL MNMO
Δ1
1
∆"
∆:
Red shift
Watkins, W. L., & Borensztein, Y. (2017). PCCP., 19, 27397.
Reminder
�SS � 10H�
�SS � 14H�
�SS � 12H� �SS � 14H�
�SS � 16H� �SS � 11H�
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
27
Edges Facets
� What is and isn’t known in the lit. ?
Hypothesis : Δ* ∝ '?�UVU5
PQ ∝ WXOYLZMLOML
The surfaces play a role in the reaction
mechanism
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
(100)
28
H – Au (100) � �[. [\ ] [. [^M_ H – Au (111) � �[. \[ ] [. [^M_
`a8a�b� � [M_
cd � 0.03U�@d � 298G
� Adsorption on the (100) or (111) ?
DFT calculations
P. Ferrin, et al, (2012) Surf. Sci.,606, 7-8, 679– 689,
Most stable surface
(111)
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
29
Adsorption on the edges Dissociation & desorption on the edges
Diffusion on the (100) facets
Desorption from the facets
1 2
3 4
Proposed mechanism
� New mechanism acknowledging the surface
(100)
H – Au (100) � �[. [\ ] [. [^M_
Most stable surface
Watkins, W. L., & Borensztein, Y. (2017). PCCP., 19, 27397.
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
30
Adsorption on the edges Dissociation & desorption on the edges
Diffusion on the (100) facets
Desorption from the facets
1 2
3 4
Proposed mechanism
� New mechanism acknowledging the surface
(100)
H – Au (100) � �[. [\ ] [. [^M_
Most stable surface
Determining the charge transfer ?
Watkins, W. L., & Borensztein, Y. (2017). PCCP., 19, 27397.
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
31
Adsorption on the edges Dissociation & desorption on the edges
Diffusion on the (100) facets
Desorption from the facets
1 2
3 4
Proposed mechanism � Adsorption on the edges 5 =�h�� � c �d��1 � =�h����i
� Desorption from the edges 5′h =�h�� � c′h�d�=�h���
� Migration from the edges ⟶facets 5�-� =�h�� , =�@mm�
� Migration from the facets ⟶edges 5′�-� =�@mm�, =�h��
� Desorption from the facets 5h =�@mm� � ch�d�=�@mm��
=�h��V
� 5h =�@mm� � 5nh =�h�� � 5�-� =�h��, = @mm � 5n�-� = @mm , =�h�� � 0
=�@mm�V
� 5�-� =�h��, = @mm � 5n�-� = @mm , =�h�� � 5h =�@mm� � 0
oMJbM : edge coverage o�\[[�: surface coverage
� Kinetic analysis : determination of the coverage in H
Measure the coverage = in H
Parameter to fitF: flowofH��w�x ∝ y�z^�Watkins, W. L., & Borensztein, Y. (2017). PCCP., 19, 27397.
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
32
F: flowofH��w�x ∝ y�z^�
Parameter to fit
� Kinetic study : measure the coverage in H
Ar H 2
Determination of the H coverage o�\[[�
Watkins, W. L., & Borensztein, Y. (2017). PCCP., 19, 27397.
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
33
� Estimation of the charge transfer
We need to know the number of adsorbed H atoms
Charge transfer per H atoms
Watkins, W. L., & Borensztein, Y. (2017). PCCP., 19, 27397.
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
34
� Estimation of the charge transfer
12 nm
4.5 nm
Equilibrium shape
T. Kizuka and N. Tanaka, (1997) Phys. Rev. B,. 56, 16, 10079–10088
Truncated octahedron
How many Au atoms?
Surface area (100)50H��⟺ 600}~?V4��
Volume400H�F⟺ 24000}~?V4��
∆*
*� �1.5 ∙ 108F
�35U8/*
1
2
∆*
*+ �
∆",���",���
= � 16%
96�4H}~�@mm�
Charge transferred per H-Au bond
�8 + �0.2U&U5)4H
Watkins, W. L., & Borensztein, Y. (2017). PCCP., 19, 27397.
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
35
� What did others find ?
Charge transferred per H-Au bond
�8 + �0.2U&U5)4H
Values from the literature : DFT
Ref. System Charge transfer
X.-J. Kuang, et al, (2013) J. of Chem. Sci., 125, 2,. 401–411. }~@F �0.1U
A. Lyalin et al, (2011)Faraday Discussions,152, 0, 26 }~�m No CT
S. Zhao, et al, (2010) J. Phys. Chem. A,114, 14, 4917–4923 }~� �0.3U
F. Libisch et al, (2013) Zeitschriftfür Physikalische Chemie, 227. }~@� �0.8U
Hu, M., et al. (2013). J. Phys. Chem. C, 117, 15050–15060. }~�� Depletion bulk N
Confirmed by DFT calculationNegative charge transfer from the NP to the H-Au bond
Watkins, W. L., & Borensztein, Y. (2017). PCCP., 19, 27397.
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
36
� Conclusion
�8 + �0.2U&U5)4H
What is the becoming of the H after adsorption ?Q
Insight into the mechanism of H2adsorption on Au
Surfaces play a role
What is the charge transfer ?QFirst quantitative experimental
results
Watkins, W. L., & Borensztein, Y. (2017). PCCP., 19, 27397.
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
37
3. Fundamental study : surface interaction of H2 with Au
o Experimental insight into the mechanismo Determination of the charge transferred
2. Fabrication of anisotropic samples
o Fabrication of Au sampleso Model the spectrao Optimising the anisotropy
4. Application study : sensing of H2 with LSPR
o Need for better optical sensing o Use of Au and Pd sensorso Use of pure Pdo Increase in sensitivity
1. LSPR fundamentals
o LSPR for sensingo Anisotropy in LSPRo Anisotropy spectroscopy
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
38
� Reactivity of Pd with hydrogen
Formation of Palladium hydride
� & �� ≫ 1%⟹ �� & �� + 1%⟹ � � �� � a^ ≪ \% ⟹ �
H/Pd
Need to detection the� phase i.e. � a^ ≪ \%
����� � 2 → 2�
Griessen, R., et al (2016). Nature Materials, 15(3), 311–317.
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
39
� Can Pd be used alone ?
Pd LSPR
LSPR in the near IRI. Zoric et al. , (2010), Adv. Mat., 22, 41, 4628–4633
AuPd
Qualitatif comparison with Au
Very large
Ext
inct
ion
[a.u
.] Abs [a.u.]
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
Wavelength(nm)
abso
rban
ce
40
� Can Pd be used alone ?
Pd LSPR
LSPR in the near IRI. Zoric et al. , (2010), Adv. Mat., 22, 41, 4628–4633
Tiny effect in the α - phase
Increase in p(H2)
Not ideal for high sensitivity sensing
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
41
� How are LSPR sensors made for H2 detection ?
Substrate
PdAu
Use Pd to absorb H2 and shift the LSPR of Au NPs
Evaporation of (0.2nm) Pd on Au
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
∆I
∆I
42
� How are LSPR sensors made for H2 detection ?
Evaporation of (0.2nm) Pd on Au
63% 16% 4% 1%
0.004%0.015%0.06%0.25%
Error gas p(H2) ≈10%
More sensitive with Pd on AuAtmospheric Pressure
(1 atm)
Room temperature (20°C)
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
43
� How are LSPR sensors made for H2 detection ?
Evaporation of (0.2nm) Pd on Au
∆I
0.004%0.015%0.06%0.25%
Error gas p(H2) ≈10%
∆IBetter with more Pd
1 nm Pd on Au
More sensitive with Pd on Au
0.001% 0.0002%
Atmospheric Pressure(1 atm)
Room temperature (20°C)
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
44
� How are LSPR sensors made for H2 detection ?
Evaporation of (0.2nm) Pd on Au
∆I
0.004%0.015%0.06%0.25%
Error gas p(H2) ≈10%
∆IBetter with more Pd
1 nm Pd on Au
More sensitive with Pd on Au
With our sensitivityis Au indispensable?
0.001% 0.0002%
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
45
� Anisotropic Pd samples : OAD
Anisotropy in the TASspectrum
Dichroism
B para
A perp
Evap. direction
Watkins, W. L., & Borensztein, Y. (2018). Sensors and Actuators B: Chemical, 273, 527–535
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
� � 0.95
46
� Model the anisotropy of Pd
B para
A perp
Evap. direction
� Calculated with effective medium theory
Reproduces the positionbut not the width
D. Aspnes, (1982) Thin Solid Films, 89, 249
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
� � 0.95
47
� Model the anisotropy of Pd
B para
A perp
Evap. direction
� Calculated with effective medium theory
Enables calculation of the hydrogenation
Distribution in f
D. Aspnes, (1982) Thin Solid Films, 89, 249
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
48
� Effect of hydrogenation on Pd
Exposure to H2 : spectrum
Strong damping of the anisotropy due to hydrogenation of Pd
Calculation of the hydrogenation
�
2����� � � → ��
� � � �h⁄ : Degree of hydrogenation
Silkin, V. M., et al(2012). Journal of Physics: Condensed Matter, 24(10), 104021
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
49
� H2 & Ar cycles with Pd sensor
∆I
Watkins, W. L., & Borensztein, Y. (2018). Sensors and Actuators B: Chemical, 273, 527–535
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
50
� H2 & Ar cycles with Pd sensor
∆I
Strong ∆: change& �� ≫ 1%
�&�?�U � UH�U
� & �� ≫ 1%⟹ �� & �� + 1%⟹ � � �� & �� ≪ 1% ⟹ �
Watkins, W. L., & Borensztein, Y. (2018). Sensors and Actuators B: Chemical, 273, 527–535
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
51
� H2 & Ar cycles with Pd sensor
∆I
Strong ∆: change& �� ≫ 1%
�&�?�U � UH�U
� & �� ≫ 1%⟹ �� & �� + 1%⟹ � � �� & �� ≪ 1% ⟹ �
Weak ∆: change& �� ≪ 1%
�&�?�U � '�~VU
Watkins, W. L., & Borensztein, Y. (2018). Sensors and Actuators B: Chemical, 273, 527–535
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
52
� H2 & Ar cycles with Pd sensor
∆I
Strong ∆: change& �� ≫ 1%
Weak ∆: change& �� ≪ 1%
Slow ∆: change& �� + 1%
�&�?�U � '�~VU�&�?�U � UH�U � � �&�?�U
� & �� ≫ 1%⟹ �� & �� + 1%⟹ � � �� & �� ≪ 1% ⟹ �
Watkins, W. L., & Borensztein, Y. (2018). Sensors and Actuators B: Chemical, 273, 527–535
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
53
Origin of the drop in ∆I
� � �� �
Drop in ∆Iphase diagram
� Thermodynamic: phase diagram (isotherm)
Can we get a quantitative measurement?
Quantitativemeasurement !
∆I
∆I
Silkin, V. M., et al(2012). J. of Phys., 24(10), 104021�∙ 108��
�∙ 108��
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
54
Quantitativemeasurement !
Most sensitive LSPR measurements of H2
Ref. Detectionlimit
Carrier gas
Response time [s]
S. Syrenova, et al., (2014) Nano Letters, 14, 5, 2655–2663 15% }5 100
’’ 4% }5 50
A. Yang, et al, (2013), ACS Nano, 8, 8, 7639–7647 2% *� 180
R. Jiang, et al, (2014), Adv. Funct. Mat., 24, 46, 7328–7337 0.2% *� �
M. Matuschek, et al, (2018)Small,14, 7, 1702990, 2018. 0.1% *� �
H. K. Yip, et al, (2017),Adv. Opt. Mat., 5, 24, 1700740 0.10% *� �
Values from the literature : LSPR with Au & Pd
� Thermodynamic: Comparison to Lit.
Watkins, W. L., & Borensztein, Y. (2018). Sensors and Actuators B: Chemical, 273, 527–535
�∙ 108��
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
55
Second import specification
Quantitativemeasurement ! Ref. Detection
limitCarrier
gasResponse
time [s]
S. Syrenova, et al., (2014) Nano Letters, 14, 5, 2655–2663 15% }5 100
’’ 4% }5 50
A. Yang, et al, (2013), ACS Nano, 8, 8, 7639–7647 2% *� 180
R. Jiang, et al, (2014), Adv. Funct. Mat., 24, 46, 7328–7337 0.2% *� �
M. Matuschek, et al, (2018)Small,14, 7, 1702990, 2018. 0.1% *� �
H. K. Yip, et al, (2017),Adv. Opt. Mat., 5, 24, 1700740 0.10% *� �
Values from the literature : LSPR with Au & Pd
� Thermodynamic: Comparison to Lit.
Most sensitive LSPR measurements of H2
Watkins, W. L., & Borensztein, Y. (2018). Sensors and Actuators B: Chemical, 273, 527–535
�∙ 108��
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
56
� Kinetic : 2 time responses
N�[Reach 90% of
signal
NJMNMZNReach readable of
signalWatkins, W. L., & Borensztein, Y. (2018). Sensors and Actuators B: Chemical, 273, 527–535
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
57
� Kinetic : In the β - phase
N�[Reach 90% of
signal
p(H2) N�[ NJMNMZN
4% β - phase 32� � 0.6�
0.25% α − phase
Watkins, W. L., & Borensztein, Y. (2018). Sensors and Actuators B: Chemical, 273, 527–535
NJMNMZNReach readable of
signal
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
58
N�[Reach 90% of
signal
p(H2) N�[ NJMNMZN
4% β - phase 32� � 0.6�
0.25% α - phase 40� � 1�
� Kinetic : In the α - phase
NJMNMZNReach readable of
signalWatkins, W. L., & Borensztein, Y. (2018). Sensors and Actuators B: Chemical, 273, 527–535
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
59
� Kinetic : In the α - phase
The faster the better !
Could we make it faster ?
Ref. Detectionlimit
Carrier gas
Response time N�[[s]
S. Syrenova, et al., (2014) Nano Letters, 14, 5, 2655–2663 15% }5 100
’’ 4% }5 50
A. Yang, et al, (2013), ACS Nano, 8, 8, 7639–7647 2% *� 180
R. Jiang, et al, (2014), Adv. Funct. Mat., 24, 46, 7328–7337 0.2% *� −
M. Matuschek, et al, (2018)Small,14, 7, 1702990, 2018. 0.1% *� −
H. K. Yip, et al, (2017),Adv. Opt. Mat., 5, 24, 1700740 0.10% *� −
p(H2) N�[ NJMNMZN
4% β - phase 32� ≤ 0.6�
0.25% α - phase 40� ≤ 1�
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
60
� Kinetic study : Setup
∆I
Desorption kinetic independent of initial p(H2)Absorption kinetic dependent of initial p(H2)
Absorption Desorption
[. ^�%
[.[�%
[.[\�%
[.[[\%
[.[[�%
Only consider0.25 %
H/P
dH
/Pd
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
[. ^�%
[.[�%
[.[\�%
[.[[\%
[.[[�%
61
� Kinetics : How does it behave ?
Absorption Desorption
Kinetic expressed in terms of H/Pd
H/P
d
H/P
d
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
62
Reaction mechanism
� Kinetics : mechanism at play
5 h�
5 ��5���
5h��
S : surface Pd V : volume Pd
� Adsorption on the surface 5 h� � c h� &�1 � =��
� Desorption from the surface 5h�� � ch��=�
� Absorption in volume 5 �� � c �� =�1 � ��
� Emptying from the volume 5��� � c �� �1 � =��
o : surface coverage � : volume H/Pd
=
V� 5 h� � 5h�� � 5 �� � 5���
�
V� 5 �� � 5���
Equations to solve to find ��V�
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
63
� Kinetics : fitting the data
• 5 h� � c h� ��1 � =��
• 5h�� � ch�� =�
• 5 �� � c �� =�1 � ��• 5��� � c �� �1 � =��
=
V� 5 h� � 5h�� � 5 �� � 5���
�
V� 5 �� � 5���
Equation set
Model fits all kineticssimultaneously
Fitted values :o c h� � 1.11 ∙ 108��)?58@
o ch�� � 0.235�8@
o c �� � 0.214�8@
o c��� � 0.111�8@
[. ^�%
[. [�%
[. [\�%
[. [[\%
[. [[�%
H/P
dH
/Pd
o : surface coverage � : volume H/Pd
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
64
� Kinetics : fitting the data
• 5 h� � c h� ��1 � =��
• OJMW � �JMW o^
• 5 �� � c �� =�1 � ��• 5��� � c �� �1 � =��
Equation set
[. ^�%
[. [�%
[. [\�%
[. [[\%
[. [[�%
H/P
dH
/Pd
1/(H
/Pd)
o : surface coverage � : volume H/Pd
Desorption limited by surface
@�����V�
2nd order
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
@�����V�
2nd order
1/(H
/Pd)
Ln (
1-H
/Pd)
65
� Kinetics : fitting the data
• 5 h� � c h� ��1 � =��
• 5h�� � ch�� =�
• OL�W � �L�W o�\ � ��• 5��� � c �� �1 � =��
Equation set
[. ^�%
[. [�%
[. [\�%
[. [[\%
[. [[�%
H/P
dH
/Pd
Desorption limitedby surface
Absorption limited by volume
ln�1 � ��h⁄ ��V�
1st order
o : surface coverage � : volume H/Pd
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
66
Absorption limited by volume
Desorption limited by surface � Self regenerates
× Improvement N�[ difficultLimited by chemistry of Pd
� Kinetics : What do we learn ?
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
∆I
∆I
67
� Use in real world conditions
Strong effect of O2 on dielectricfunction of Pd
Effect of air & H2O (4% H2 in air | 50% humidity)
∆I
Unreactive when left in air
20% O2
Effect of O2 on Pd
Still reactive in dry & humid air (4%)
Dry air 4% Humid air 4%
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
Could we make it faster ?
68
� Conclusion
With our sensitivityis Au indispensable?Q
High sensitivity reached in the α phaseeven with only Pd
QKinetics limited by Pd / H2 chemistry
� High sensitivity� Auto regenerates� Wide range of p(H2)� Rapid response time� Works in air
� Quantitative reading in the α phase � Limited by the phase diagram of Pd� Kinetics limited by the Pd chemistry
Practical achievements Fundamental achievements
Watkins, W. L., & Borensztein, Y. (2018). Sensors and Actuators B: Chemical, 273, 527–535
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
69
PERSPECTIVES
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
70
� Use of Metal Organic Frameworks as filters
� Choice : ZIF-8
� Expectations :
Permeable to H2 and not O2 nor H2O
Zn(NO2)2 +
Nano porous protective layer
Koo, W.-T., et al (2017). ACS Nano, 11(9), 9276–9285.
imidazoleZinc nitrate
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
71
� Use of Metal Organic Frameworks as filters
Pd 1st coat 2nd coat
Nano porous protective layer
Collaboration ENS - ESPCI : - Pr Christian Serre- Dr Antoine Tissot- Shan Dai
Koo, W.-T., et al (2017). ACS Nano, 11(9), 9276–9285.
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
72
� MOF in air cycles
Cycles in dry air
Does not prevent oxidation of sample, but still sensitive
Cycles after multiple days
…but still reactive
Different mechanism in air…
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
73
� Application in liquid medium
May be used for other type of sensing ex: protein , heavy metals, etc…
Fabrication of liquid cell
Direct industrial application
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
74
CONCLUSION
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
75
5 h�
5 ��5���
5h��
� Summary and conclusion
Techniques
Capabilities
Fundamental
Patent : FR1859255
Δ1
1
Differential
More sensitive LSPR measurements
OAD allowsSimple & effective
anisotropic samplesSingle wavelength
monitoring
TAS allows
Application
� Enables fundamental investigation of surface reactivity ideal for catalysis
� Direct application : H2 sensing � But also : biochemistry,
green chemistry
ConclusionIntroduction LSPR fundamentals Anisotropic samples H2 with Au Sensing of H2 Perspectives
76
INSP
� Yves Borensztein� Emmanuelle Lacaze� Geoffroy Prévot� Sébastien Royer� Bernard Croset
� Dominique Demaille� Loïc Becerra� Erwan Dandeu
� Acknowledgments
Collaborations
� Fabienne Testard
� Christian Serre� Antoine Tissot� Shan Dai
PhD Co-workers
� Alberto Curcella� Léo Bossard-Giannesini� Emmanuel Puig
Physico-chimie et dynamique des surfaces (PHYSUF)