Photoluminescence, photocatalytic and antibacterial activities of CeO2·CuO·ZnO nanocomposite fabricated by co-precipitation method.

A novel tri-metallic oxide nanocomposite CeO2·CuO·ZnO has been synthesized by a simple co-precipitation method. The nanocomposite has been characterized by XRD, SEM, EDS, FTIR and PL spectra. The crystallite size of the CeO2·CuO·ZnO was calculated using XRD data. The crystallite size of the CeO2·CuO·ZnO mixed metal oxide annealed at 600 °C is found to be in range of 15.34-44.81 nm, with an average size of 29.51 nm. Excitation at different wavelengths showed PL in UV and visible regions. It has been found that PL behavior of CeO2·CuO·ZnO is excitation wavelength dependent. This flexible PL property is conflicting to well-known Kasha's rule of excitation wavelength dependence of emission spectrum. The catalyst shows better photo-catalytic dye degradation efficiency in slightly alkaline pH in presence of H2O2. Nanocomposite CeO2·CuO·ZnO was found to be effective against pathogenic bacteria.

Synthesis, characterization, PL properties, photocatalytic and antibacterial activities of nano multi-metal oxide NiO⋠CeO2⋠ZnO.

A novel multi-metal nanocomposite, NiO⋅CeO2⋅ZnO has been prepared by co-precipitation of their carbonates from aqueous solutions of the metal nitrates following calcination and annealing 5 h at 450°C and 10 h at 950°C. NiO⋅CeO2⋅ZnO has been characterized by XRD, SEM, EDS, IR and PL spectra. The crystallite size of the as-synthesized sample varies in the range of 14-23 nm and those of the annealed sample in the range of 17-50 nm. Emissions of NiO⋅CeO2⋅ZnO have been observed in UV (NBE emission) and visible region at different excitations. Excitation wavelength dependent PL behavior of NiO⋅CeO2⋅ZnO has been observed in acetone at room temperature. This PL property is in disagreement with Kasha's rule of excitation wavelength dependence of emission spectrum. Photocatalytic as well as anti-bacterial activities were studied.