Speaker
Description
In this work, five (05) samples of YBCO have been synthesized via sol-gel
technique. The samples were prepared by varying the concentrations of polyvinylpyrrolidone
(PVP), keeping all other reaction parameters constant. The synthesized samples were then
characterized by X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy
Dispersive Analysis of X-rays (EDAX), Transmission Electron Microscopy (TEM/HRTEM)
and Fourier Transform Infrared Spectroscopy (FTIR). From the XRD analysis, information
regarding the crystallite structure of the samples has been obtained. From SEM analysis,
information regarding the surface morphology, shape and size of the synthesized samples has
been obtained and the elemental composition of the sample has been confirmed from the
EDAX data. Using TEM analysis, the particle size of the YBCO nanoparticles were observed
to be in the range 10 nm to 70 nm having mostly spherical shape. Formation of distinct rings,
observed from the SAED pattern indicated the highly crystallite nature of the sample. From
FTIR analysis, information regarding the functional groups of the synthesized samples has
been obtained. From the XRD analysis, it has been confirmed that, changing the concentration
of PVP, during the preparation of the samples, resulted in the formation of nanoparticles
having varying crystalline sizes. The average crystalline size of YBCO nanoparticles
decreased with increase in PVP concentration.
After successful synthesis of the 05 different YBCO nanocomposite samples as
discussed above, we have attempted to study the variation in resistance of the samples, with
variation in temperature, in a temperature range starting from 0 0 C to 75 0 C.
