AuNP-SWCNT dispersions

Figure 6.26 Results from analysis of the final AuNP-SWCNT dispersions performed using (i) UV-Vis spectroscopy, showing the AuNP SPR peak and [ii) TEM, showing the AuNP PSD. Scale bar in fii) represents 200 nm.

For composites prepared with AuNP-SWCNT dispersions, the ratio of SWCNTs and AuNPs in the final composite was fixed. It would, however, be interesting to study any changes in the percolation network of the SWCNTs as a function of AuNP loading. To achieve... 

Composites prepared with a variety of PSS/AuNP/SWCNT dispersions were examined and the final percolation thresholds are given in Figure 6.27, along with the control system where only SWCNTs are present. The series are defined as follows ... 

AuNP Series 1. PSS/AuNP/SWCNT dispersion used. 

The synthetic procedure for the preparation of AuNPs as reported by Zhang et al. was followed. Solutions of PSS and of the block copolymer synthesized, as well as SWCNT dispersions prepared with the various polymers, were used as scaffolds in the synthesis of AuNPs. 

The quantitative characterization of the AuNP/SWCNT reactions proved to be problematic. Some baseline scatter was observed due to the presence of the SWCNTs. To avoid scattering during UV-Vis analysis of SWCNT dispersions, the concentration of SWCNTs was kept very low. At these low sample concentrations, it was difficult to get a strong absorption band from the AuNPs. It was, however, still... 

Figure 6.23 Schematic of the final dispersion after the synthesis of AuNPs physi-sorbed onto PS-b-PDMAEMA-covered SWCNTs.

AuNP Series 2. PSS/SWCNT and PSS/AuNP dispersions used together. 

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