Supplementary Material (ESI) for Journal of Materials Chemistry
This journal is © The Royal Society of Chemistry 2011
[Electronic Supplementary Information]
Reproducible Synthesis of Silver Colloidal Particles Tailored for
Application
in
Near-Infrared
Surface-Enhanced
Raman
Spectroscopy
Robert Prucek,a Ales Panacek,a Jana Soukupova,a Radko Novotny,b and Libor Kvitek*a
a
Regional Centre of Advanced Technologies and Materials, Department of Physical
Chemistry, Faculty of Science, Palacky University, 17. listopadu 1192/12, 771 46 Olomouc,
Czech Republic. Fax: +420 585 634 761, Tel: +420 585 634 420, E-mail:
[email protected]
b
Laboratory of Microscopic Methods, Faculty of Medicine and Dentistry, Palacky University,
I. P. Pavlova 35, Olomouc 771 26, Czech Republic.
Supplementary Material (ESI) for Journal of Materials Chemistry
This journal is © The Royal Society of Chemistry 2011
Fig. S1: The UV-Vis absorption spectra of silver particles prepared via the reduction of the
complex anion [Ag(SO3)2]3- by hydroquinone (A) and 1,4-phenylenediamine (B) in
dependence on the concentration of sulfite in the reaction system.
Supplementary Material (ESI) for Journal of Materials Chemistry
This journal is © The Royal Society of Chemistry 2011
Table S1: Average particle diameter, polydispersity, and half-width of the size distribution
obtained from DLS method and average particle diameter obtained from the TEM images of
silver particles prepared via the reduction of the complex anion [Ag(SO3)2]3-.
hydroquinone
reducing
agent
catechol
Ascorbic
phenylenediamine
phenidone
4-aminophenol
1,4-
acid
c (sulfite)
[mol.L–1]
average
particle
diameter [nm]
polydispersity
half-width of
lognormal size
distribution
0.2
0.1
0.05
0.02
0.01
0.005
0.2
0.1
0.05
0.02
0.01
0.005
0.2
0.1
0.05
0.02
0.01
0.005
0.2
0.1
0.05
0.02
0.01
0.005
0.2
0.1
0.05
0.02
0.01
0.005
0.2
0.1
0.05
0.02
0.01
0.005
210
191
188
186
187
195
298
233
205
197
196
187
262
233
222
215
210
212
722
368
210
205
207
199
693
409
212
200
201
200
667
375
222
210
208
203
0.218
0.211
0.203
0.213
0.187
0.194
0.184
0.149
0.142
0.175
0.186
0.193
0.178
0.177
0.145
0.152
0.169
0.188
0.244
0.186
0.168
0.148
0.163
0.168
0.222
0.198
0.184
0.182
0.183
0.190
0.210
0.134
0.152
0.155
0.160
0.191
103
89
84
86
79
83
109
91
74
82
85
81
110
96
84
85
87
93
372
154
86
77
82
80
318
175
89
84
85
88
282
142
89
83
84
94
average particle
diameter [nm]
obtained by TEM
200
190
190
180
170
180
260
230
210
190
200
180
250
230
230
210
200
200
710
370
220
200
210
200
600
390
240
220
210
190
600
350
230
200
210
200
Supplementary Material (ESI) for Journal of Materials Chemistry
This journal is © The Royal Society of Chemistry 2011
Table S2: The changes of the potential of the silver electrode with the concentration of
sulfite. The values of electrode potentials were calculated according to the equation (3).
concentration of Na2SO3
redox potential of the system
[mol·L–1]
Ag+/Ag [V]
0.2
0.191
0.1
0.228
0.05
0.264
0.02
0.312
0.01
0.349
0.005
0.391
Table S3: The values of the redox potentials and dissociation constants of the used reducing
agents.1
Reducing agent
Eo [V]
EpH=11 [V]*
pK1
pK2
hydroquinone
0.709
0.091
9.91
11.56
catechol
0.760
0.162
9.25
12.37
ascorbic acid
0.375
0.085
4,14
11.44
p-phenylenediamine
0.846
0.139
2.70
6.20
p-aminophenol
0.785
0.105
5.65
10.40
phenidone
0.690
0.135
9.35
–
*values of the redox potentials of the reducing agents (at pH=11) was calculated using the
corresponding Nernst-Peters equations.
Supplementary Material (ESI) for Journal of Materials Chemistry
This journal is © The Royal Society of Chemistry 2011
Table S4: Comparison of the number of the as-prepared silver particles via the reduction of
the complex anion [Ag(SO3)2]3- by hydroquinone at different silver nitrate concentrations.
c(AgNO3)
[mmol·L–1]
average particle
diameter*
[nm]
approx. number of
particles per mL
0.250
160
1.198·109
0.150
130
1.339·109
0.100
110
1.471·109
0.075
100
1.470·109
0.050
90
1.560·109
* the average value of the particle diameter as determined from the TEM images
References:
1
T. H. James, The Theory of the Photographic Process, MacMillan Publishing Co.,
New York, 1977.