Synthesis and fluorescence properties of Ag nanoparticles

Ag nanoparticles synthesized by employing an electro-exploding wire technique exist in face-centered cubic phase with average size ∼10 nm. A surface plasmon peak is observed at ∼400 nm. Study of fluorescence properties of Ag nanoparticles shows fluorescence peaks at ∼300 nm for excitation wavelength in the range 220–270 nm. In concomitant with these, resonant absorptions are observed at ∼215 nm and ∼270 nm, which allow us to establish the electronic levels operating in the Ag nanoparticles system. Also, intensity of fluorescence emission increases with increase in concentration of Ag nanoparticles till a critical concentration. For the first time, we report temperature dependence of fluorescence of the Ag nanoparticles in the temperature range 20–90 ∘C. Where, the intensity of the fluorescence peak at ∼300 nm decreases with increase in temperature. Also, in conformity with these, probability of resonant absorption decreases with increase of temperature and with change in position of emission wavelength from maximum intensity.