Correlation of structural, adsorption and optical properties of novel polymer capped Dy:ZnNiO and Ce:ZnNiO nanocomposites

• Highly crystalline composites.
• Nanostructured particles due to the effects of polymer.
• High specific surface area with mesoporosity.
• Low defect energy by the effects of surface passivation.
• Highly enhanced ultraviolet emission by suppressing defect level green emission.

Synthesis of rare-earth metals (Dy, Ce) doped ZnNiO (Dy:ZnNiO and Ce:ZnNiO) nanocomposites using polyvinylpyrrolidone (PVP) as the capping molecules has been accomplished using the wet chemical route. Structural and optical properties of surface modified Dy:ZnNiO and Ce:ZnNiO are examined. X-ray diffraction indicates that all of the as-obtained samples can be indexed to hexagonal structure. Correlation between the structural and optical properties was studied for the synthesized nanoparticles. The crystallite sizes of the composites depend on the level of disorder, albeit to a limited extent, where minimum disorder matches with high crystallinity. Significant functional correlation could be found between the differences in experimentally observed crystallite size and Urbach energy. Specific surface area and pore size of the composites confirmed the mesoporous nature of the samples. The fluorescence spectra of the samples show, the effects of surface passivation in the ultraviolet emission region.