Structural modifications and extended optical properties of Ni1-xCoxWO4 nanoparticles

We studied the effect of cobalt doping on structural and optical properties of NiWO4 nanoparticles. Different compositions of cobalt-doped NiWO4 were synthesized using direct chemical precipitation method. X-ray diffraction patterns of Ni1-xCoxWO4 nanoparticles revealed variation in average crystallite size and micro-strain without any change in the standard crystal structure. Transmission electron microscopy studies showed a deviation of particles size and morphology of the samples with a change in dopant concentration. Raman and Fourier transformed infrared spectroscopy also confirmed the standard NiWO4 profiles at different doping ratios. UV-VIS-NIR spectroscopy gave the information related to the bandgap tuning with the change in dopant concentration. It is also confirmed dual direct-indirect nature of bandgap in Ni1-xCoxWO4 nanoparticles. Photoluminescence emission spectroscopic studies displayed variation in emission spectra and colour with cobalt doping. [Display omitted] •Ni1-xCoxWO4 nanoparticles are prepared by a simple, eco-friendly chemical precipitation route.•First report for the investigation of structural and optical properties of Ni1-xCoxWO4.•The results of the optical studies confirmed the direct-indirect band gap nature of Ni1-xCoxWO4 .•Ni1-xCoxWO4 phosphor can be suitable for lighting applications.