M. Rathnakumari

Studies on electrical properties of MgO/Pr6O11 nanocomposite

Magnesium Oxide/Praseodymium Oxide (MgO/Pr6O11) nanocomposite was prepared by sol–gel method. X-ray diffraction analysis confirmed the cubic structure. The morphology was studied using high-resolution scanning electron microscopy picture. The AC/DC conductivity and dielectric properties were investigated in the frequency range of 1–4 KHz and in the temperature range of 303–573 K. The results showed that the dielectric constant and the tangent loss were frequency and temperature dependent. The AC/DC conductivity at different temperatures indicated that the conductivity was thermally activated. The activation energy for AC/DC conductivity was calculated using Arrhenius plot.

Effect of solvent and annealed temperature on band gap energies of MgO nanoparticles

Novel two-dimensional nanostructures of magnesium oxide nanoparticles were synthesized by simple reflux method by changing the solvent and annealing temperature. The structural and surface morphology were investigated using X-ray diffraction spectra and High-resolution scanning electron microscopy (HR-SEM). The XRD spectrum showed that the synthesized MgO samples are pure cubic MgO. The HR-SEM picture showed that the MgO nanoparticle prepared with ethanol as a solvent gives different morphologies such as nanoflakes, nanoflowers and nanosheet at low temperature. At high temperature, the flake shape changes into spherical shape. The micro strain is calculated using Williamson-Hall plot method. The optical properties of synthesized MgO nanoparticle studied by using UV-Visible and Photoluminescence (PL) spectra. UV emission and a broad visible emission band in photoluminescence (PL) spectra further demonstrates that the potential applications of the material in optoelectronics. The particle size, morphology and band gap of the synthesized MgO nanoparticle is highly influenced by the solvent and annealing temperature.

Synthesis and Study of Optical properties of MgO based TM oxide (TM=Cu, Mn and Zn) nanocomposites

A nanocomposite of MgO based transition metal (TM) oxide (TM=Zn, Mn, and Cu) was synthesized using sol-gel method. The powder x-ray diffraction confirmed the phase purity and particle size. The surface morphology and elemental composition were examined by High resolution scanning electron microscopy and energy-dispersive x-ray spectroscopy. The change in optical band gap of the synthesized nanocomposites, by increasing the Mg content was determined using UV–vis spectra and the luminescent properties were analyzed using photoluminescence spectra.