Silver Metal Nanoparticles: Facile Dendrimer Assisted Size Controlled
Synthesis and Selective Catalytic Reduction of Chloronitrobenzenes
Amy Sutton, Grégory Franc and Ashok Kakkar*
Department of Chemistry, McGill University,
801 Sherbrooke St. West, Montreal, Quebec H3A 2K6 Canada
Supporting Information
1.
The G2 dendrimer templated silver nanoparticle synthesis in dark.
Intensity (counts)
2000
1500
38.5
(111)
1000
500
44.7
(200)
64.9
(220)
77.8
(311)
82.3
(222)
0
30
40
50
60
70
80
90
2theta (degrees)
Figure 1. XRPD of G2 dendrimer templated silver nanoparticles in the absence of light.
1
2.
Synthesis of silver metal nanopartilces using DHBA protected with Me3Si groups:
Intensity (counts)
2000
1500
1000
500
0
30
40
50
60
70
80
90
2theta (degrees)
Figure 2. XRPD of the solid particles from the reaction of the G0 dendrimer with protected
hydroxyl groups in the absence of light.
Intensity (counts)
2000
1500
1000
500
0
30
40
50
60
70
80
90
2theta (degrees)
Figure 3. XRPD of the solid particles from the reaction of the G0 dendrimer with protected
hydroxyl groups in the presence of light.
2
3.
3,5-Dihydroxybenzyl alcohol (DHBA, G0) based silver nanoparticles:
G0 dendrimer was also used to synthesize silver nanoparticles, however, it required a
slightly different methodology. DHBA (25 mg, 0.18 mmol) was added to 5 mL of a previously
made aqueous silver acetate solution (41.7 mg/1.9 mmol in 25 mL), and under vigorous stirring,
the reaction mixture was heated to ~40°C for three hours. The colour changes were much slower
as the solution went from a clear yellow to orange, and then to brown and grey. The resulting
nanoparticles were too few to make a TEM sample without greatly increasing the scale of the
reaction. For these reasons, a direct comparison with the results from the other three generations
is not particularly meaningful. A UV-Vis spectrum of the G0 nanoparticle sample is shown in
Figure 4 below. The absorption was weaker than for the other samples. The peak at 350 nm
corresponds to DHBA, and the peak at 440 nm to the nanoparticles.
2
1.8
1.6
Absorbance (au)
1.4
1.2
1
0.8
0.6
0.4
0.2
0
300
400
500
600
700
Wavelength (nm)
Figure 2. UV-Vis
Spectrum of the G0 dendrimer based nanoparticles.
3
4. TEM images of the G1 Dendrimer templated silver metal nanoparticles:
A) TEM (220k) of G1 templated silver nanoparticles using fast addition. B) TEM (340 k) of
silver nanoparticles from G1 dendrimer using slow addition. C) TEM (300k) of silver
nanoparticles from G1 dendrimer using slow addition and dilute solution.
4