Silver nanoparticles have been prepared by photoreduction of silver nitrate with 254 nm UV light in the presence of poly(N-vinylpyrrolidone). The effects of PVP concentration on the particle size, the UV−vis absorption peak, and the rate of the photoreduction process were studied. The average particle size ranged from 15.2 to 22.4 nm, with the corresponding UV−vis absorption peak position at 404−418 nm in 1−0.25 wt % PVP. The rate of the photoreduction process was observed to increase with the PVP concentration. X-ray photoelectron spectroscopic studies further revealed that the polymer interacts with silver particles through the oxygen atom in the >CO group. A negative shift of binding energy in the Ag 3d5/2 for silver nanoparticles was observed.

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The effects of annealing on the structural properties of radio-frequency sputtered amorphous silicon carbide films prepared under different hydrogen partial pressures (PH) were investigated. Infrared (IR) results of the as-prepared films suggest that as PH increases, more hydrogen is incorporated into the film to form the Si–H and C–H bonds and less silicon and carbon atoms are available to form the Si–C bonds. X-ray photoelectron spectroscopy (XPS) results of the as-prepared films agree with the IR results in that the percent of Si–C decreases and the percent of Si–H and C–H increases as PH increases. IR and XPS results of the annealed films suggest that as the annealing temperature increases, the dangling Si and C bonds will combine to form the Si–C bonds for the unhydrogenated samples. The increase in Si–C bonds for the hydrogenated samples is more likely to be due to the formation of Si–C bonds from the breaking up of the Si–H and C–H bonds.

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