PHYS01200704032 Debes Ray - Homi Bhabha National Institute

SPR Peak Absorbance
Absorbance
Chapter 4: Optimization of the Block Copolymer-mediated Synthesis of Gold Nanoparticles
(a)
0.6
0.4
0.0 wt% HAuCl4.3H2O
0.002 wt% HAuCl4.3H2O
0.004 wt% HAuCl4.3H2O
0.006 wt% HAuCl4.3H2O
0.008 wt% HAuCl4.3H2O
0.010 wt% HAuCl4.3H2O
0.012 wt% HAuCl4.3H2O
0.014 wt% HAuCl4.3H2O
0.016 wt% HAuCl4.3H2O
0.018 wt% HAuCl4.3H2O
0.020 wt% HAuCl4.3H2O
0.2
0.0
440 500 600 700 750
Wavelength (nm)
(b)
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.0
0.000 0.004 0.008 0.012 0.016 0.020
[HAuCl 4
.3H 2
O] in wt%
Figure 4.3. (a) The gold salt concentration normalized SPR peak in UV-visible absorption
spectra of 1 wt% P85 with varying concentration of HAuCl 4 .3H 2 O in aqueous solution.
(b) Variation of SPR peak absorbance in UV-visible absorption spectra.
Figure 4.2 is magnified for clarity in Figure 4.3(a). The SPR peak height increases with salt
up to 0.008 wt% concentration in consistent with the colour variation seen in Figure 1. The
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