Enhanced dielectric and optical performance of (Cu, Ag) co-doped ZnO nanostructures for electronic applications

Abstract

ABSTRACT Pure and Cu/Ag co-doped ZnO nanoparticles were synthesised by the co-precipitation method. The phase and structural analysis of ZnO nanoparticles were examined by using XRD and Williamson-Hall plots. XRD spectra revealed that prepared samples exhibit hexagonal wurtzite structure of ZnO. The change in lattice parameters, bond length, dislocation density and strain indicates that Cu and Ag were successfully incorporated. UV vis studies indicated the red shift in the absorption band attributed to defects induced after dopant additions. The dielectric measurements showed that the dielectric constant was found to increase and the dielectric loss decreases with increase in dopant percentage. Additions of Cu and Ag in ZnO lattice may lead to supplement grain boundary defects which can increase polarisation. The relatively higher values of ac conductivity were also found due to modulation of charge carrier density after dopant additions which suggest that the diffusion controlled charge carrier hopping mechanism is involved.