Structural, optical and ferroelectric behavior of CuO nanostructures synthesized at different pH values

In this paper, we have reported the structural, optical and ferroelectric properties of copper oxide nanostructures synthesized by hydrothermal method at different selected pH values ranging from 4 to 12. The synthesized nanostructures were characterized for structural properties by X-ray diffractrometer and transmission electron microscopy and the optical properties were carried out through UV-visible, Photoluminescence and Raman spectroscopy. The study of X-ray diffractrometer pattern indicates the pure phase formation of CuO and Transmission electron microscopy images show the structural changes from nanorods to rectangular nanoflakes for samples synthesized at higher pH values. Raman and Photoluminescence spectrum also confirm the phase formation of CuO nanostructures. Moreover, the optical band gaps calculated through UV-visible spectroscopy are found to be increases from 2.90 to 3.60 eV for samples synthesized at pH values from 4 to 12 respectively. Furthermore, a weak ferroelectricty has been observed for pH 10 and 12 samples at room temperature through Polarization vs Electric field (P-E) loops. (C) 2013 Elsevier Ltd. All rights reserved.