Supporting Information. for. Advanced Materials, adma Wiley-VCH 2005

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1 Supporting Information for Advanced Materials, adma.5391 Wiley-VCH Weinheim, Germany

2 Supporting information for: Synthesis of Metal-Teflon AF Nanocomposites by Solution- Phase Methods By David D. Evanoff, Jr., Paul Zimmerman, George Chumanov Figure S.1. IR spectra of Ag(fod) [Silver(I) 6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5- octanedionate] used in 1 the one-step synthesis procedure. Spectra were collected on a 8 Nicolet 55 Magna-IR spectrometer. KBr pellets were prepared using a 1:1 ratio of 6 KBr to Ag(fod). Figure S.1.B is a selected region of Figure S.1.A A B

3 Figure S.2. IR spectra of silver/teflon AF nanocomposite synthesized using the one-step synthesis procedure. Spectra were collected on a Nicolet 55 Magna-IR spectrometer. KBr pellets were prepared using a 1:1 ratio of KBr to nanocomposite. Figure S.2.B is a selected region of Figure S.2.A. When comparing the spectra in Figure S.1 with those in Figure S.2, it is apparent that the salt anion is not present in the nanocomposite powder. In Figure S.1.A, the peaks at ca. 285cm -1 and 165cm -1 most likely represent the alkane C-H stretch and the unsaturated ketone C=O stretch, respectively, of the anion. These peaks are completely absent in the spectrum of the silver/teflon AF 85 nanocomposite powder. Moreover, the IR spectrum of the nanocomposite 65 powder coincides very well with the IR spectrum of pure Teflon AF shown in Ref. 11. This data 45 indicates that the particles in the A nanocomposite are stabilized by the Teflon AF matrix and not by residual salt anions B

4 Figure S.3. Particle Size Distributions for one-step synthesis reactions Gold Size Distribution Mean: Median: 16 Standard Deviation: 15 %Frequency Silver Size Distribution Mean: 18 Median: 16 Standard Deviation: Palladium Particle Distribution Mean: 8 Median: 7 Standard Deviation: Nickel Size Distribution Mean: 1.8 Median: 1.7 Standard Deviation:.5

5 Figure S.4. A representative STEM image and the corresponding size distribution graph showing the mean diameter of gold particles prepared by the one-step synthetic procedure. The procedure differed from that described in the main text in that the ratio of polymer to metal salt was doubled. When comparing the size of these particles to those shown in the main text, it is obvious that varying the amount of polymer added to the reaction mixture can vary the resulting particle size in the nanocomposite Gold Size Distribution 16 Mean: 9 14 Median: 9 12 Standard Deviation: Figure S.5. Spectra showing the result of the two-step, phase transfer reaction for the incorporation of 15 nm silver particles into Teflon AF. The blue spectrum is bare silver particles suspended in 2-propanol. The black spectrum is that of the silver/teflon AF nanocomposite suspended in Vertrel XF. The plasmon band shape did not change significantly, indicating that the particle size 1.6 distribution and aggregation state is not appreciably affected by the incorporation. The blue shift in the spectrum is caused by the decrease in the local 1.2 refractive index around the particles from that of 2- propanol to that of Teflon AF. Optical Density wavelength (nm)

6 Figure S.6. Representative STEM image showing large (ca. 15 nm) silver nanoparticles after being incorporated into Teflon AF by the two-step, phase transfer procedure. Because the particles are synthesized prior to incorporation into Teflon AF, the particle diameter and size distribution can be completely controlled. Also, it is apparent from the figure that the incorporation reaction does not damage the particles in any way. Figure S.7. Spectra showing the decrease in the plasmon resonance of a silver/teflon AF nanocomposite after one hour exposure to the vapors of a boiling 5.2M HNO3 solution. After the blue spectrum was taken, the nanocomposite solution was evaporated and the dry nanocomposite exposed to the acid. After one hour, the nanocomposite was rinsed with methanol, dried and resuspended in the same amount of Vertrel XF as used in the original solution. The spectra indicate that after one hour, practically no particles have been etched by the acid vapors. Extinction Wavelength (nm)