Microwave-Assisted Synthesis of Silver Nanoparticles: Effect of Reaction Temperature and Precursor Concentration on Fluorescent Property

Abstract

The fluorescent silver nanoparticles were synthesized using trisodium citrate as a reducing and stabilizing agent in a microwave-assisted reduction process. The influence of synthesizing parameters such as reaction duration, temperature, and trisodium citrate concentration (100, 200, and 400 ppm) were examined on the characteristics and fluorescent properties of synthesized silver nanoparticles (AgNPs). The formation of AgNPs was studied by UV–Vis absorption spectroscopy, X-ray diffraction, ATR-FTIR spectra, and scanning electron microscopy. The low concentration compared to the high concentration of trisodium citrate resulted in a prolonged reduction process, and also the high concentration resulted in the formation of smaller AgNPs (44 nm). The fluorescence emission spectra of the synthesized colloidal AgNPs demonstrated a quite explicit emission peak centered around 335 nm. However, the higher reaction temperature (above 100 °C) resulted in a sharp and narrow emission peak. The synthesized silver nanoparticles exhibited a suitable fluorescent property, which was reliant on the size of synthesized AgNPs.