Optical and Dielectric Properties of Nano GdAlO3

Abstract

Nano perovskite-type structure as denoted by ABO3 (A= RE) have been popular targets of fundamental investigations since they exhibit a wide variety of physical properties depending upon the chemical composition, defects and small changes in atomic arrangements. Nanocrystalline GdAlO3 is synthesized through a modified combustion process. The X-ray diffraction study shows that the nanopowder is single phase with orthorhombic structure and belongs to the space group Pnma. The FT-IR spectral analysis confirms that the as-prepared powder itself is phase pure. The UV-Vis spectrum analysis reveals that the material is a wide band gap material with band gap of about 5.7eV along with good transmittance in the visible region which makes it suitable for transparent conducting oxide films for window layers on solar cells. Refractive index of the sample as a function of photon energy is also measured. The high value of optical conductivity in the visible region indicates that nano GdAlO3 is ideal for the fabrication of solar cell panels. Photoluminescence spectrum at the excitation wavelength 260nm is also recorded and analyzed. The dielectric constant, loss factor and conductance are studied in the radio frequency region. The conductance is very small at radio frequencies and is of the order of 10-6Ω-1 in the MHz frequency range. The low conductance and loss factor confirm its suitability as a promising candidate for application as substrate and electronic packing materials.