Optical band gap, Urbach energy and Defect related Photoluminescence in Ni0.95 Al0.05O Nanostructure

Abstract

The Ni1-xAlxO (x = 0.05) nanocrystalline synthesized by chemical route using sol gel method calcined at 600 °C. Scanning electron microscopy (SEM) has been carried out to study the morphology for our sample. In addition, UV-visible spectroscopy has been carried out to determine the optical band-gap energy (3.92 eV) via Tauc model with associated Urbach (EU) energy (1.78 eV) that confirms the increased disorder with Al (x=0.05) incorporation into NiO lattice. The deconvoluted PL spectrum using Gaussian function of sample exhibits violet and green emission when NiO is doped with Al (x=0.05) which are indicative of Ni interstitial (Nii) and oxygen vacancy (Vo), respectively.