Title : Enhanced photoluminescence and fluorescence properties of flake-like Co3O4@Cs2O bimetallic oxide nanostructures
Abstract:
Hybrid nanostructures (NS) were increasingly used as fluorescent and photoluminescent applications. In the present study, Co3O4@Cs2O bimetallic oxide nanostructures were synthesized by simple precipitation method. The as-synthesized NS were characterized by XRD (X-ray diffraction), SEM (scanning electron microscope), EDX (energy dispersive X-ray), XPS (X-ray photoelectron spectroscopy), BET (Brunauer-Emmett-Teller) and UV-visible analytical methods. XRD revealed the mixed phase of hexagonal crystal structure. Agglomerated flake like morphology of the Co3O4@Cs2O NS observed in SEM studies. Red shift in optical absorptivity appeared as the Co2+dopant concentration increases on Cs2O lattice with decrease in the optical band gap from 3.25 eV to 3.0 eV. The photoluminescent studies of Co3O4@Cs2O NS at different excitation wavelength (λ excitation), i. e at 250 nm, 280 nm and 320 nm showed emission intensities of 432 nm, 480 nm, 545 nm, 620 nm respectively related to the formation of oxygen vacancies. The decrease in the intensity of UV-visible intensity of the peaks attributed to the formation of the defects and distortion in the crystal structure after doping. However, room temperature PL spectra showed broad emission peak at 460 nm to 580 nm. Fluorescence studies of Co3O4@Cs2O NS showed peaks at 452 nm. The synthesize nanostructure is promising candidate for optoelectronics and photonic applications.
