Excitation-induced tunable luminescence of luminomagnetic Dy and Ce co-doped ZnO nanoparticles.

Here, 1 mol% Dy,Ce co-doped ZnO nanoparticles were synthesized via a simple, cost-effective combustion method which could produce large-scale products. The structure and phase purity of synthesized nanoparticles were shown by X-ray diffraction, selected-area-electron-diffraction patterns and Raman spectroscopy to be a hexagonal wurtzite structure with no secondary peaks. Spherical morphology was shown by field emission scanning electron microscopy and high-resolution transmission electron microscopy. The presence of dopants with elemental composition was authenticated by energy dispersive spectroscopy and elemental mapping. Enhanced reflectance in the visible region for Ce-doped ZnO samples was noted by diffuse reflectance spectroscopy. An increase in the bandgap for doped samples was indicated by the Kubelka-Munk function. Significant visible luminescence was observed, which varied with different excitations. The room-temperature weak ferromagnetic behaviour of 2 mol% Ce-doped ZnO and distinct paramagnetic behaviour of 1 mol% Dy,Ce co-doped ZnO was detected using vibrating sample magnetometry.