Synthesis and characterization of AgI-Ag₂O-SeO₂ glass-nanocomposites embedded with β-AgI and Ag₂SeO₃ nanocrystals

Abstract

Glass-nanocomposites of compositions xAgI-(1-x)(0.40Ag₂O-0.60SeO₂) for 0.15≤x≤0.30 were prepared by quenching the melt of the appropriate mixtures of the chemicals AgI, AgNO₃ and SeO₂. Differential scanning calorimetry (DSC) was employed to determine the glass transition and crystallization temperatures. The as-prepared samples were heat-treated above glass transition temperature to observe the growth of nanoparticles. X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM) were used to explore the microstructure of these samples. These studies revealed the presence of β-AgI and Ag₂SeO₃ nanocrystals in both the as-prepared and heat-treated samples. The particle size was found to decrease with the increase of AgI content in both cases. The heat-treated samples showed increased tendency of crystallization for the compositions with higher AgI content. The β-α phase transition of AgI crystals was observed at ~147-149°C for heat-treated samples. Fourier transform infrared (FTIR) spectra revealed that the basic structure of the glassy network remained invariant to change of AgI content as well as to heat-treatment.