Upconversion luminescence of cerium doped CoWO4 nanomaterials

In this paper we report the bluish green upconversion intrinsic photoluminescence (PL) observed at room temperature (RT) 300 K for the nanorange (27–50 nm) Ce3+ doped and undoped CoWO4 powder samples sintered in air at 600°C. Excitation by Xenon lamp at 600 nm was done and the emission was observed between 400 nm and 550 nm. Co1−xCexWO4 [where x=0.00, 0.02, and 0.03] compounds were prepared by the solution based co-precipitation method and characterised by X-ray powder diffraction (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The surface morphology of the compounds was examined by scanning electron microscopy (SEM) techniques. Optical absorption and photoluminescence behaviour of the compounds in the rigid matrix were studied. High emission intensity and easy preparation make these systems potential candidates for application as luminescent materials. - Highlights: ► Ce3+ doped CoWO4 nanosamples were prepared by the co-precipitation method. ► Characterised by XRD, TEM, SEM and XPS. ► Upconversion intrinsic luminescence observed for nanosamples. ► Mechanism for the upconverted emission is explained. ► No upconverted luminescence observed for bulk samples.