Isha Saini

Refractive Index Tailoring of Poly(methylmethacrylate) Thin Films by Embedding Silver Nanoparticles

Nanocomposite films of Poly (methylmethacrylate) with different concentration of silver nanoparticles were prepared by ex-situ method. Firstly, silver nanoparticles were obtained by reducing the aqueous solution of silver nitrate with sodium borohydride then Ag-PMMA films were prepared by mixing colloidal solution of silver nanoparticles with solution of polymer. Thin solid films were structurally characterized using UV-VIS spectroscopy and TEM. The appearance of surface plasmon resonance peak, characteristic of silver nanoparticles at 420 nm in UV-VIS absorption spectra of Ag-PMMA films confirms the formation of Ag-PMMA nanocomposite. TEM showed Ag nanoparticles of average size 8 nm embedded in PMMA matrix. Analysis of absorption and reflection data indicates towards the reduction in optical band gap and increase in refractive index of the resulting nanocomposite. The synthesized Ag-PMMA nanocomposite has been found to be more conducting than PMMA as ascertained using I-V studies. The decrease in band gap and increase in conductivity can be correlated due to the formation of localized electronic states in PMMA matrix due to insertion of Ag nanoparticles. The PMMA thin films with dispersed silver nanoparticles may be useful for nanophotonic devices.

Tailoring of optical and electrical properties of PMMA by incorporation of Ag nanoparticles

Silver–poly(methyl methacrylate) (Ag–PMMA) nanocomposite films were prepared via ex situ chemical route by employing sodium borohydride (

Tuning of optical properties of PMMA by incorporating silver nanoparticles

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Tailoring of electrical, optical and structural properties of PVA by addition of Ag nanoparticles

NaBH4) as a reducing agent. In this study, PVP-stabilized Ag nanoparticles were prepared and mixed with PMMA solution. Optical and structural characterizations of resulting nanocomposite films were performed using UV–visible spectroscopy, transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Characteristic surface plasmon resonance (SPR) peak of Ag nanoparticles was observed at about 3.04 eV (408 nm) in absorption spectra of Ag–PMMA nanocomposite films. TEM micrograph revealed that the spherical Ag nanoparticles with an average diameter of 5.4

Spectroscopic analysis of Ag nanoparticles embedded in glass

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Modification of structural, thermal, and electrical properties of PVA by addition of silicon carbide nanocrystals

±2.5 nm are embedded in PMMA. In Raman spectra, besides shifting of vibrational bands, enhancement in intensity of Raman signal with incorporation of Ag nanoparticles was observed. Current (I)–voltage (V) measurements revealed that conductivity of PMMA increased with increasing concentration of Ag nanoparticles. Analysis of I–V data further disclosed that at voltage <2 V, ohmic conduction mechanism is the dominant mechanism, while at voltage >2 V Poole–Frenkel is the dominant conduction mechanism. Urbach’s energy, the measure of disorder, increased from 0.40 eV for PMMA to 1.11 eV for Ag–PMMA nanocomposite films containing 0.039 wt% of Ag nanoparticles.