摘要 :
In the present work we report the characterization of PbO-GeO_2 films containing silver nanoparticles (NPs). Radio Frequency (RF) co-sputtering was used for deposition of amorphous films on glass substrates. Targets of 60PbO-40GeO...
展开
In the present work we report the characterization of PbO-GeO_2 films containing silver nanoparticles (NPs). Radio Frequency (RF) co-sputtering was used for deposition of amorphous films on glass substrates. Targets of 60PbO-40GeO_2 (in wt%) and bulk silver with purity of 99.99% were RF-sputtered using 3.5 m Torr of argon. The concentration of silver and gold NPs in the films was controlled varying the RF-power applied to the targets (40-50 W for the PbO-GeO_2 target; 6-8 W for the metallic target). The films obtained were annealed in air at different temperatures and various periods of time. Absorption measurements have shown strong NPs surface plasmon bands. Different widths and peak wavelengths were observed, indicating that size, shape and distribution of the silver NPs are dependent on the deposition process parameters and on the annealing of the samples. X-Ray Fluorescence and Transmission Electron Microscopy were also used to characterize the samples.
收起
摘要 :
The influence of the temperature on the nucleation of silver nanoparticles (NPs) in Tm~(3+)/Yb~(3+) codoped PbO-GeO_2 glasses was studied in this work. The infrared-to-visible frequency upconversion (UC) luminescence of Tm~(3+) io...
展开
The influence of the temperature on the nucleation of silver nanoparticles (NPs) in Tm~(3+)/Yb~(3+) codoped PbO-GeO_2 glasses was studied in this work. The infrared-to-visible frequency upconversion (UC) luminescence of Tm~(3+) ions was used to probe the NPs nucleation and the results were correlated with the increase of the heat-treatment temperature. Emission spectra in the blue-red region were measured by exciting the samples with a cw 980 nm diode laser in resonance with the Yb~(3+) transition (~2F_(7/2) → ~2F_(5/2)). The results were correlated with transmission electron microscopy measurements and revealed the different behavior of the nucleation process as a function of temperature. The enhanced UC emission in the visible region is attributed to the increased local field in the proximity of the silver NPs combined with the Yb~(3+) → Tm~(3+) energy transfer.
收起
原文获取