Photocatalytic Performance of Pristine NiO and Ni6MnO8 Nanopowders in Degradation of Rose Bengal Dye

Abstract The present paper describes synthesis of nickel oxide and Ni₆MnO₈ nanopowders by simple hydrothermal technique. During the synthesis of nickel oxide by hydrothermal process addition of Mn source resulted in the formation of Ni₆MnO₈. X-ray diffraction analysis has confirmed the formation nickel oxide and Ni₆MnO₈ both having cubic structures. The average crystallite size decreases from 20 nm to 12 nm on increasing Mn source concentration during the synthesis of nickel oxide. Rectangular, hexagonal and triangular faceted structures were revealed from the scanning electron microscopic images. Ni₆MnO₈ nanopowder found to display optical bandgap around 2.65 eV. The photocatalytic properties of synthesized nickel oxide and Ni₆MnO₈ nanopowders were measured by using Rose Bengal dye under UV illumination. Enhancement in the photocatalytic activity was noticed in the case of Ni₆MnO₈ nanopowder as compared to nickel oxide nanopowder. Nearly 90% dye degradation was observed on utilizing Ni₆MnO₈ nanopowder.