This study focuses on the synthesis of aluminum oxide nanoparticles (AlO-NPs) hydrogel through in situ method and formation of biopolymer nanocomposite film. UV-Vis spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy (TEM), particle size analyzer, and energy dispersive X-ray spectrum were performed for the characterization of AlO-NPs. TEM micrograph demonstrates the presence of AlO-NPs in the range of 50-100 nm in the hydrogel network made from sugarcane bagasse carboxymethyl cellulose (SB-CMC) and synthetic carboxymethyl cellulose (CMC). The successful absorptions peak at 210 nm while conducting UV-Vis spectroscopy suggests existence of AlO-NPs. The antibacterial properties of AlO-NPs were analyzed using the disc plate diffusion technique against Gram-negative bacteria: Escherichia coli (ATCC 433); and Gram-positive bacteria: Bacillus subtilis (ATCC 1688). AlO-NPs present in CMCs films reduce moisture content, solubility; elongation at break and increases films' tensile strength.

In the present study, we have synthesized composites of gold (Au) nanorods with reduced graphene oxide (rGO) and characterized using UV-Visible spectroscopy and Transmission Electron Microscopy (TEM). The formation of graphene oxide (GO), rGO, Au nanorods and composite of rGO-Au nanorods have been confirmed using UV-Visible spectroscopy. The morphological studies have been done using TEM. Further, the surface Plasmon Resonance (SPR) behaviour of prepared Au nanorods has been tried to simulate using Discrete Dipole Approximation (DDA).

In the present study silver, gold and their alloy (Au1-xAgx (x = mole fraction of gold)) nanoparticles have been prepared under microwave irradiations. The prepared nanoparticles have been characterized using UV-Vis spectroscopy and high resolution transmission electron microscopy (HRTEM). The observance of single Surface Plasmon resonance (SPR) peak in the absorption spectra of Au1-xAgx alloy solutions attributed to the homogeneous formation of bimetallic alloy nanoparticles. There is linear red shift in observed SPR peak with increase in mole fraction (x). TEM images reveal the spherical shape of prepared Au1-xAgx alloy nanoparticles with average size ranging from similar to 4 - 17nm. The observed SPR peak have also been simulated using Mie Theory and DDA method.

The present paper represents the facile and rapid synthesis of reduced graphene oxide-silver (RGO-Ag) nanocomposite with the help of microwave irradiation. The graphene oxide (GO) solution has been prepared in bulk using Hummer's method followed by microwave assisted in-situ reduction of GO and silver nitrate (AgNO3) by hydrazine hydrate in a short spam of 5 min. The prepared nanocomposite has been characterized using Transmission Electron Microscopy (TEM), X-Ray Diffraction (XRD) Scanning Electron Microscopy (SEM) and UV-Visible spectroscopy. TEM analysis shows that Ag nanoparticles with average size 32 nm are uniformly entangled with in RGO layers. The UV-Visible absorption spectrum of nanocomposite depicts the reduction of GO to RGO along with the formation of Ag nanoparticles with the presence of characteristic surface Plasmon resonance (SPR) peak of Ag nanoparticles at 422 nm. The performance of prepared nanocomposite has been tested as the active Surface Enhanced Raman Scattering (SERS) substrate for Rhodamine 6G with detection limit 0.1 mu M. (C) 2017 Elsevier B.V. All rights reserved.

In this work, nanocomposites of reduced graphene oxide-poly (vinyl alcohol) (PVA) grafted with silver nanoparticles (rGO-PVA-Ag) were prepared in the absence and presence of rose water. The optical characterizations of prepared nanocomposites were done through UV-visible spectroscopy and Transmission Electron Microscopy (TEM) and Raman spectroscopy was employed for the surface characterization. The grafted silver (Ag) nanoparticles are found to be almost spherical in shape with reduction in their mean diameter from 47 nm to 26 nm after addition of rose water. The UV-visible absorption spectra of as-prepared rGO-PVA-Ag nanocomposites without and with rose water depicted surface plasmon resonance (SPR) peak at around 448 nm which coincides with the predicted spectra from simulation based on the Mie Theory. The electrical dc conductivity measurements as the function of temperature from room temperature to 55 degrees C were investigated. It has been found that use of rose water in synthesis process increases the electrical conductivity of the rGO-PVA-Ag. The mode of the electrical conduction in the composites can be explained using Efros-Shklovskii Variable Range Hopping mechanism (ESVRH).

In the present study, metal (Ag and Cu) nanostructures were prepared in presence of ethylene glycol using PVP with the aid of conventional household microwave. The microwave assisted methods enjoy the obvious advantages of symmetric and volumetric heating, ease of synthesis and decreased time of reaction. The choice of Ag and Cu is attributed to their large catalytic activity, high antibacterial capability, prominent Surface Enhanced Raman Scattering (SERS) etc. The characteristic Surface Plasmon Resonance (SPR) peak for these nanostructures confirms their formation. Further, shape and morphological studies were done through Transmission Electron Microscopy. The as prepared fast, rapid and green synthesis of Ag and Cu nanostructures may found applications in SERS, electrochemical and biological sensors etc.