Annu Sharma; Jyoti Rozra; Isha Saini
Abstract
In the present work, effects of annealing temperature on structural and optical properties of silver-glass nanocomposites synthesized by the combined use of ion-exchange and subsequent thermal annealing in air have been investigated using Transmission electron microscopy (TEM), UV–Visible absorption ...
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In the present work, effects of annealing temperature on structural and optical properties of silver-glass nanocomposites synthesized by the combined use of ion-exchange and subsequent thermal annealing in air have been investigated using Transmission electron microscopy (TEM), UV–Visible absorption spectroscopy and Photoluminescence spectroscopy. The appearance of SPR peak characteristic of silver nanoparticle formation around 429 nm in absorption spectra of silver-glass nanocomposite samples indicates towards the formation of silver nanoparticles in glass. The size of silver nanoparticles has been found to increase with increase in annealing temperature. At an annealing temperature of 200°C the size of silver nanoparticles comes out to be 2.31 nm which increases to a value of 7.60 nm at an annealing temperature of 550°C. TEM investigation indicates that silver nanoparticles of size 6.57+1.14 nm are formed in glass matrix. UV-visible absorption and reflection data has been analyzed to ascertain optical properties such as absorption coefficient (α), refractive index (n) and dielectric constant (ε). Emissions bands in the photoluminescence spectra were analyzed to investigate different oxidation states of silver present in the prepared nanocomposite samples. Formation of Ago atoms from Ag + ions are responsible for the quenching of photoluminescence intensity at higher temperature. Such nanocomposites are expected to be promising materials for ultrafast optical switches and for sensing applications.
Jyoti Rozra; Isha Saini; Sanjeev Aggarwal; Annu Sharma
Abstract
Structural and optical properties of Ag-glass nanocomposite, synthesized by the combined use of vacuum deposition method and subsequent thermal annealing have been studied using UV-Visible absorption spectroscopy, Field emission scanning electron microscopy (FE-SEM) along with Energy dispersive analysis ...
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Structural and optical properties of Ag-glass nanocomposite, synthesized by the combined use of vacuum deposition method and subsequent thermal annealing have been studied using UV-Visible absorption spectroscopy, Field emission scanning electron microscopy (FE-SEM) along with Energy dispersive analysis of X-rays (EDAX), Transmission electron microscopy (TEM) and Photoluminescence spectroscopy. Ag-glass nanocomposites were synthesized by depositing Ag on glass slides and the resulting samples were annealed at various temperatures from 300°C to 550°C for 1 hour. The fingerprint feature of Ag nanoparticles formation i.e. the surface plasmon resonance peak is observed around 427 nm in absorption spectra of Ag-glass samples annealed at various temperatures, this confirms the formation of Ag nanoparticles in glass. The size of Ag nanoparticles has been found to increase with increase in annealing temperature. At an annealing temperature of 400°C the size of Ag nanoparticles comes out to be 4.6 nm which increases to a value of 10.0 nm at an annealing temperature of 550°C. TEM micrograph further confirms the formation of Ag nanoparticles of size 8 + 2 nm at an annealing temperature of 550°C. Further, analysis of UV-Visible absorption and reflection data indicates towards the increase in refractive index of Ag nanoparticles doped glasses. It has been established that with the insertion of Ag nanoparticles of size 8 + 2 in glass the refractive index of the resulting nanocomposite increases to a value of 1.96. The dispersion parameters such as single-oscillator energy Eo, and the dispersion energy Ed have been discussed in terms of the Wemple-DiDomenico single-oscillator model. Photoluminescence spectra of silver glass nanocomposite have been studied and observed spectroscopic features have been correlated with various transitions of silver ions. Such studies are vital for designing optical materials for example optical communication, photonic devices etc.