Defects studies in as-synthesized and neutron-irradiated Mn, Li co-doped ZnO using Positron Annihilation Spectroscopy

In this work, we report the Doppler broadening Positron Annihilation Spectroscopy (PAS) studies of the as- synthesized and neutron irradiated Mn and Li co-doped ZnO nanocrystals (Zn 0.96-x Mn 0.04 Li x O for x =3D 0.00, 0.02, 0.03, 0.04), synthesized by low-temperature co-precipitation method. Samples were characterised by X-ray diffraction and the XRD patterns confirmed single phase Wurtzite hexagonal structure of all the samples. The samples were irradiated by neutrons obtained from a 5.0 Ci AmBe neutron source with a flux ~ 3.3×10 5 n/cm 2 -sec at irradiation position. Positron annihilation Doppler broadening spectroscopic measurements were carried out and calculated S and W parameters were plotted against Li doping concentration for the as-synthesized and the neutron irradiated samples and the findings have been discussed in terms of magnitude and nature of the defects induced.