Investigation of physicochemical characteristics of Dy3+ modified ZnO nanoparticles

Abstract

In this report, pristine and Dy3+ modified ZnO nanoparticles [Zn(1-x)DyxO NPs, where x = 0, 0.05, and 0.10] were synthesized using the sol–gel route, and their physicochemical characteristics were investigated. x-ray diffractograms of all the compositions possess P63mc space group depicting hexagonal crystallinity with wurtzite-type crystal structure with no signature of impurities as confirmed using the Rietveld refinement technique. The granular microstructure displayed grain growth with Dy3+ incorporation in the ZnO crystal framework and an increment in average grain size was found to be 22.83 nm for x = 0 to 36.34 nm. The optical energy band gap also increased from 3.35 eV to 3.88 eV with Dy3+ doping in the host ZnO. Dy3+ substitution inhibits the conduction in ZnO and improves the resistivity (36 Ωcm–79 Ωcm) as carrier concentration diminishes from 7.36 × 1016 cm−3 to 4.23 × 1016 cm−3. Similarly, the mean free path length for ZnO and Dy3+ doped ZnO NPs declines from 0.0301 nm to 0.0198 nm. Dielectric properties of all the compositions were investigated using an LCR impedance analyzer and it was observed that Dy3+ substitution enhances the value of the dielectric constant from 32 to 91 with a low tangent loss at 50 Hz.