Superior dielectric behaviour and band gap tuning of Zn doped MgO nanoparticles

Abstract

ABSTRACT The primary aim was to study the doping effect of Zn in MgO nanoparticles (NPs) prepared by the co-precipitation method. X-ray diffraction (XRD) results inferred the cubic structure of MgO with good crystallinity, which changed with dopant additions. Scanning electron microscope (SEM) images exposed the development of NPs with decreasing size and dimensions with little agglomeration on doping. Fourier transform infrared (FTIR) results revealed the Mg-O bond formation, which is associated with Zn-O bond on increasing dopant content. UV Vis studies showed the red shift in absorption edge and decreased band gap with percentage of Zn dopant additions. The dielectric results exposed the dielectric constant, dielectric loss and ac conductivity of Zn-doped MgO NPs. Dopant addition led to the higher dielectric constant and low dielectric loss at lower frequency due to oxygen vacancies generation. The impedance behaviour in different frequency regimes illustrated the effective contribution of conductive grains and insulating grain boundaries.